Not changing what I wrote, but in writing this I realized that I had not played with planar shifting enough for targeting, only using it when it was absolutely necessary because of where the target was, and scrolling up and immediately down does circumvent some of these, and maybe all of these, targeting issues, which is great, but still unideal. The issues with targeting shouldn't show up at all and if there is no easy way to stop that occurring then it should be noted in game that planar shifting will allow the targeting to work more correctly. I've played through the main campaign twice, started a couple where I just wasn't interested in the party I created, have played a few created campaigns, and I'm looking to start another in lost valley where I play a band of elitist High Elves that kowtow to Orentis' every whim. While my lack of exploration in the controls might seem like an outlier, why would I expect my ability to target to change and not just suspect the engine was designed with some things overlooked? I am introduced early on in the game to the limitations experienced without there ever being a need for (and really before the introduction of) planar shifting, they are already accepted and being worked with, they appear to be simply how the game was built. I could have been lucky and found out by accident earlier or tried to cast before moving my plane and found then that I could target differently, but I didn't.
1) Spider climb has far more limitations than should be expected because walls are often not coded as walkable or somesuch. To wit, in lost valley there is an area with the rebels where there are air drakes (?) and an air elemental and to the left of the door on the upper floor there is a section partitioned off by a wall but that has a plant. You can fly there. You can misty step there. You can dimension door there. Despite there being a wall connected to the ground floor with a very clear path up to that area and despite being able to walk on the wall leading up to the landing with the door by using spider climb (fun fact, they are the same wall) you can't use spider climb to walk up that clear path. A diagram, since there are no screenshots for whatever reason:
| | ________
| | | DOOR |
|_P______|__________|_______|______________
|XXXXXXXOOOOOOOOOOOOOOOOOOOOOOOO
|XXXXXXXOOOOOOOOOOOOOOOOOOOOOOOO
|XXXXXXXOOOOOOOOOOOOOOOOOOOOOOOO
p is the plant.
|X is where I cannot climb up for whatever reason
O is where I can
Another area was in the library in the original campaign where all the spiders show up and there's a chest and there are definitely walls going all the way to touch the landing holding said chest. No, you're forced to get the ability to do one of those things mentioned before. Continuing on this limitation, there is no reason why I as a player using spider climb cannot simply choose a point on a wall to go to, which is glaringly missing despite the spiders and soraks in game being able to do so.
2) Same area as in the diagram, there are 2 platforms that none of my characters could climb up to, which is annoying considering they are on pylons of perfect climbing width and easy to grab, also still inaccessible with spider climb for still strange reason, but that's not the issue. The issue is that despite being able to get on these platforms by other methods (misty step or flying) I found that if those methods were not then available, I would be stuck. Fall damage is a thing. Let my characters jump down and hurt themselves instead of forcing a reload for no good reason. It makes more sense to have a jump be available and trap a member than for a member to become trapped because they cannot jump down.
3) Per the tooltip: "Curse of Time: Starting at the 1st level, whenever you damage an opponent with a spell, they become afflicted with the Curse of Time. Enemies under the Curse of Time take half your proficiency bonus (rounded up) force damage at the start of their turn for the next minute."
Except it seems to proc only once per round (turn, maybe, but I don't know of anyways to opportunity attack with cantrips and I hadn't run hellish rebuke, I nixed the build once I realized this interaction) despite not stating that it only procs once per round. Or maybe once per spell. I had taken magic missile so I could readily apply curse of time to disparate enemies at the start of the encounter and lo! it only applied on the first target. Maybe this works well with fireball and properly applies there, but it does not properly apply "whenever you damage an opponent with a spell" nonetheless.
4) Per the tooltip: "Arcane fury: Add your proficiency bonus and INT bonus to your evocation spell damage for 1 minute."
Again, it is only once, either per turn or per cast, though maybe potentially per target. I do not recall if it procs on everyone when I cast fireball and hit multiple people, and when I use magic missile or scorching ray, which provides unique instances of damage, I am tending to focus a single target. It kindly tells me, after blasting the poor sap with 8 instances of evocation spell damage, that Arcane fury did a whopping 8 extra damage and not 64. This one in particular I suspect to be a clarification issue because getting 8 shots off of magic missile would be 8d4 + 8 + 64 ((4 prof. + 4 int. mod) * 8) to average 96 damage guaranteed to hit (barring shield) compared to the normal average being 32 damage (cast at 5, treated as 6 for arcane warfare) and comparing against disintegrate's (Actually cast at 6 because it's not evocation) 75 damage on a save or suck...well, that's a bit much innit? As written, it is what should be expected, though in actuality it isn't what occurs.
5) Readying a cantrip and setting a preference can be overridden... to your detriment! I didn't want to use scorching bolt despite the enemy definitely going to come in range of it before ray of frost because I knew fire damage in fact healed the sonofabitch. So why would you force my character to shoot fire at them, especially considering they would later, in that same turn, without their movement ever stopping, come into range of ray of frost? This is an issue with ready action being obtusely limited.
6) Let me ready an action against specific targets. I might not give a rat's ass about one of the enemies coming into range and might care more about another, especially when I can slow them down (ray of frost, eldritch blast w/hindering blast invocation) or move them (eldritch blast w/ repelling blast invocation), or when there are aoe spells like spike growth down that I expect to do most (if not the rest) of the work killing an enemy but they just so happen to be moving before the other enemy.
7) Not to mention I don't know why I can't ready a spell. I imagine this is implementation, though. And frustration at the original ready action from the SRD making it to where the spell slot is consumed even if the spell isn't cast even though all of the things occurring in a round are supposed to be happening simultaneously. I guess I can make a sword attack in that small time frame (of a ready action being triggered) but not just cast a spell even though it is supposed to be the same exact time frame? But that's a gripe not to be levied here.
8) Sometimes I can attack enemies with cantrips requiring line of sight but can't cast aoe spells/abilities targeted at the same spot. I can point to a spot in lost valley. At the outpost, climbed the lone tower to the southwest of the outpost to start the battle. anyway, just to the left of the rampart there stood a guy. My druid had call lightning up (more on that later) and was up the ladder. he had line of sight to all the people on the left of the rampart there. He was standing on the corner, the wooden platform connected to the stone tower. And he could cast venomous spike on this guy who would be one space over just below him. But call lightning is better. I never got to use that call lightning because despite having line of sight to everyone; that wasn't enough. Let me cast aoe in the areas where I can see the space just above it where entities would reside. Maybe I cannot see the ground, but you be damned sure I can still blow a lightning bolt through that man's dome.
9) Speaking of aoes, holy crap is placing an aoe so difficult. They are limited by what is able to walked upon and so simple things like bags on the ground that I am not allowed to walk upon become places where I can't center. Not too much of an issue when it's just one spot, but there are sometimes patches that I can't use as the center forcing me to not use spells because I can't actually target them effectively. And at the edge of a map? where the demarcation is some soft little shrubs? Or an incline? The map limitations shouldn't really be the determinant of the spell placement. Hell, hypnotic pattern using the ground as its base is horrendous for this. It's center is in the air! I assume this is implementation, but it makes things needlessly difficult to use. And call lightning "conjures a storm cloud" so why am I not able to place it over any area (granted that I'm like outside or something) and have the entire underneath targetable?
10) The only nuisance that I put on here that I fully understand. Line of sight is used for everything, and many things, like fireball, don't actually need it SRD. But this is a game where I can see everything all the time and the limitations of not being able to know where something is because of obscured vision so casting fireball is built on hopes and dreams are lost. But it's still annoying that I cannot throw a fireball into a fog cloud while out of it. There are other such annoying interactions. And here's the thing: I played tabletop. I knew the position of enemies even when my character had obscured vision. Granted, there was a DM and maybe some more honesty in playing, but probably not a whole lot. It's only with the whole advent of modern vtts that the DM can effectively remove that knowledge from an individual player. But that hasn't stopped those spells not requiring line of sight.