add custom abilities to classes, revamp some old ones.
as an example, I'll be reworking vampire.
Make them slower and their sprint speed slower, still faster than other players, but not by much. Lower the sun damage, and make it work like minecraft mobs, where you only take damage if you dont have anything above you. Add either 2 abilities. Teleportation, or a bat mode (which they bat mode is cooler, but harder to code.) The teleportation is simple, start teleporting for about half a second, gaining speed and being able to phase through walls. This also makes you invincible and invisible. after the time is over, all buffs are removed and youre back to youre normal state. For the bat mode, it'll be more complex. Be able to fly, or get an air jump similar to Kirby while in the bat mode, letting you fly to escape scenarios. This lasts for about 20 seconds, but you can cancel it early. It makes you faster and smaller, but you take more damage. This mode won't make you take damage from the sun. Adding an ability like this to a few classes could really make the game funner and make the game more replayable.