Ok it took a LONG time to do that, and a lot of it had to do with the game not cooperating at ALL.
The most infuriating and frustrating part of me doing a play test is when the game decides to roll all 1s and all 20s. Nothing cheezes me off more than that. When you do a playtest you want average rolls to establish what an average play will be, and one side getting either all 1s or sub 5 rolls in a game is as useless as getting all 15+ rolls. Its useless and tells me nothing about the combat. So you can imagine how many combats I had to restart when the algorythm starts to hose up like that. Because it tells me nothing,
Anyway... first of all congrats on your first module. .
1. Good placement of loot in the starting party chests. Some people forget that you really do need to include things like alternate item slot items for things like Spell Focuses and Holy Symbols. Rangers, Paladins, Clerics, and Wizards all have to use them and they cannot afford to blow their usable items slot on a component pouch, or Clerics may need that neck slot. Paladins and Rangers specifically need their usable items slot open because they are most likely to use it. Good job on including those. Also... cool idea with dividing the items into magical and non-magical chests I liked it.
2. I know you used primarily Pre-Fabs and didn't do your own design for rooms... and that's ok since this is your first one. But just a note... when you do start to branch off and do more of your own personalizing. You would want a little more rubble in the initial hallway opening part. You give a Lore description, but the hallway looks too clean to match your word description. Don't be afraid to choke that baby up with rubble the party has to jump over and squeeze around to really feel like its a rubble strewn and collapsed hallway.
3. Get rid of the Fires and Braziers in the secret areas where there's no traffic. One of the things that builds the "this place is not used" feel, is when its actually not lit up, since, well there's no one around to light them in those areas so there would be no fires there. It will really help build the atmosphere you're going for.
4. Careful of putting Lore triggers in combat areas, in your case, because they weren't overly wordy you can actually read them before they disappear, but there were a couple I missed that got spammed off before I could read them. Overall though you did a good job on the putting in Lore triggers to provide a backstory to help build the mood of the dungeon well.
5. Good job hiding your crawlspace. That was pretty well done. I may have found it but I did notice your attempts to hide it. The downside though is, you didn't really do much to hide your Secret Doors. In this game you really have to put things in front of a secret door to keep it from being discovered because Caution mode picks them up from a LONG ways away. And sometimes leaving them in obvious areas is like broadcasting there's a secret door there. I'm not talking about your intentional ones that you mean to be discovered, moreso the ones you didn't mean to. Example: That one in the final fight.
6. The undead encounter was excellently designed, and very believable in the context of what you wanted to do. But that is an example of a secret door you may want to hide better, since this was one of your intended secret areas. Still the actual encounter was really good and believable. Again douse the lights though.
7. Might be a few too many Magical bows as treasure. I think I had 4 of them combined with a Heavy Crossbow which is a 1d10 ranged weapon. That was probably too many and I couldn't use them all anyway. So you might want to swap one or two of them for something else.
8. Excellent choices for actual combat areas which included the specific prefabs with cover and walls a good "war zone" per se.
8. Nice job on the ending, that was probably the best you were going to be able to do for the resolve because of what we were given to work with. It was a very creative solution.
But now we get to the problem area...
You asked me this question earlier today and I didn't really answer you but I really think I should... You asked me... why I didn't use Goblin Shamans in every encounter with the Ogres to make it more challenging in Hall of the Ogre Lord. And you felt I should to "make it more of a challenge" with magic using creatures.
The real answer to this question is... context of the world. Sure I could just throw an Archmage or Shock Wizard or some other caster just for kicks... but this misses the point. You were thinking too much in terms of "game" and 1s and zeros... not enough in terms of the context of the world.
One of the things that creates a believable world, is not just throwing any random creature in there because you can or to make it a challenge as it makes your world and atmosphere much less believable.
Believe it or not people really get into these things and emotionally involved in them when the context of the world around them is believable.
Why are there a TON of level 1 Orcs in Ruined Keep of Agramar? Its not just because that's the only orc in there... because even if we had Orc Berserkers or Orc Chieftains I still would not be throwing entire groups of those at the players, I might have one small room of Elites like that but that would be the only one. I'd be doing it like a real encounter
35 Orc Archers
In the context of the world this is what you would see, it makes it believable no matter how many puny orcs you squash along the way at 5th level... or spam the screen with. Its not done to spam the screen,
The only thing I might have done would have been to swap out some of the Ogres for Orc Berserkers, That would be the only change. I also wouldn't be adding a caster to every encounter just to make it harder, because again that wouldn't match the context of the world. When you are taking on Ruined Keep of Agramar... it really DOES feel like an actual Orc Hold because you get swarmed by so many Orcs.
With that in mind... I'll move on to your encounter schemes...
The real context of the world... a normal human like a merchant or commoner is what you'd call a 0 level creature. Kinda like a Kobald, they only have 1/2 hd and a soldier is only a Level 1 Fighter. There are tons of these and they are the ones who are assigned as sentries and guards.
a 5th+ level Fighter is never the guy on local guard or watch duty. So throwing a bunch down because they're tough really makes an encounter unrealistic in the context of the world. I know you might be thinking... but but but this will make it more "challenging"... yeah but it won't make it believable in the context of the world. The more of this you do the less immersive it becomes.
A 5th level fighter (aka multi-attacking fighter) is an Elite Soldier, Kinda like our special forces. A Viscount would not have these. These would be only the special soldiers of a King or Ruler of the land and he'd never waste them on minor guard duty like that.
So when you're designing a Guard Post encounter if you wanted to make it credible and believable, it would be
20 1st level Fighters
2 2nd level Sergeants
1 5th level Watch Commander
Ergo... throwing down 4 5th/6th level Bandit Captains just feels completely off. You need something smaller. Remember those are the leaders. Its not about just 1's and zeros.
If you really wanted the adventure you were going for... you should have made it a lower level adventure than 7th-8th if you wanted to give it a challenge and a realistic one in the context of the world.
Now by context you COULD have pulled that off in the large room as a group of Elite Mercenaries as a special encounter... but then the problem became the other things you threw in there with them. You could have gotten away with the large number of Spies. But once you threw in all the Clerics along with it... it became a serious question of... what exactly are all these clerics doing here?
One or two might have been ok... but you had like 8 of them in there which made no sense.
I kept asking myself what are all these Clerics doing here?
Then in your final encounter (I found the secret door by the way)
I suddenly walked into 4 Archmages and 4 Evil Clerics which again had me asking the same question. What is this screwy group all doing together?
I could not find any "Underground Temple" in your creations, so it made no sense, And I sure as heck couldn't find a Mage Academy anywhere which is the ONLY place you'd see that many High Level Mages in one place at one time.
So at this point I'm going, ok he just threw down a bunch of random junk with no coherency.
If you see a High Level Mage he will be alone, unless he's part of a Magic Circle. He might have a couple of lower level apprentices, but not a ton of High Level mages.
What was a High Priest doing there? The Warlord I could believe because he would have been the Guard Captain or Leader of guards we'd seen up to that point... but the High Priest? 4 Archmages and a Shock Wizard plus another 4 Evil Priests?
This was the only real problem you had in your module really was your encounter design there is no coherency in them at all and they are unrealistic in the context of the world.
Think in terms of what the actual world around you would be when you're designing these.