"Outside of battle, dungeons will now feature fixed designs, instead of being random"
This could be amazing depending on how you work this. You can have traps, both in and out of combat, you could switch up the dungeon mid-game (like shift rooms). Teleporter, damage, puzzles! I say go all out if you want to go this route. Maybe add in a hub-world as well.
I really like the sound of reworked combat too, it sounds really fun. Cheers!