How to improve?
1. Implement actions closer to 5e
2. Improve AI so they do a thorough search
3. Fix broken code- like attacking an enemy and combat is never started.

There is also a difference between solo/full party stealth and typical party play.
After watching too much TY DnD (lol): have the rogue attack and try to hide.. and the enemies mostly ignore the rogue to focus on the Barb and Paladin in front of them is fine.

But-
Rogue attacks then hides, then the AI stands there saying "ill get you, you cant get away" and does nothing, then the rogue attacks and hide.rinse and repeat is not a fun game imo. Hence i save sneaking for out of combat