Sneaking is the ultimate engagement strategy, the benefits are top notch (+1 round with surprised enemies, first attack with advantage, chance to stay hidden on successful stealth roles, etc.)
Sneaking (cautious) is incentivized to be always on in order to adress the player need of not "missing out" on secret doors, footsteps, etc.
This leads to a player behavior of always sneaking, unless one really doesn't care. But playing seriously and properly, it is the way to go.
So when playing seriously, the game design basically incentivizes that mode to "always on", in turn standardizing movement speed to a crawl, which negatively affects game flow and playability, as waiting times increase for characters to reach destinations, and the general feel of the pace of the game goes down the drain.
Basically the design puts the player into a position of 2 bad choices:
-Player at normal speed and flow, but suffer gameplay disadvantages.
-Play with gameplay advantages, but suffer out-of-game disadvantages (annoyed feelings, waiting times, slow gameplay).
-Besides being annoyed by the sluggish pace, there is no in-game game-play relevant factor to not always be in cautious mode.
This is a bad concept, if the reason to not use it is out-side of game punishment.
-Stealth should be handled like on the world map travel. Either you suprise the enemy upon encounter, or you don't. Independent of cautious state. Encounter settings could further define if a stealth-start of combat is even possible for that particular encounter.
-Stealth also breaks some encounters in a weird way, where the enocunter is spawned by triggers (presumely portraying an ambush), but the monsters do not see the party when combat starts, because the party is in stealth.
-Increased perception should not be tied to cautios mode, but instead distance to object. That way finding hidden things is not promoting permanent cautious mode, but instead the player has to actively navigate the characters close to possible secret doors, buttons etc.
This would also increase the player's connection the to leveldesign, as the need is not to just "pass along in cautius mode" but to actively engage in the specifics of the environment.
(e.g. walking 2 or even 1 grid next to the wall that then gets hilighted as a secret door.)