Lets start with
leveling: i believe it would be nice to have a stand gain increase damage the more its used. It would be a hamon breathing type thing the only difference being it dosnt reset after a day or periodically go down. Leveling abilitys could be as simple as just attacking enemies or mining with your stand. (And obviously damage wouldnt rise at a insane rate)
If not then we move onto
Custom resolve amount: In the config you can edit the damage of a stand but you cant edit the resolve amount to reach that damage, usually its stuck at 3-5. Normally this wouldn't be an issue but alot of times i use this mod i a company it with other mods that eventually outclass stands making them useless. If you added a custom resolve amount then you would be able to periodically gain more damage (by setting the power higher) with each resolve.