With the Custom starter kit, players can select their own kit and unlock it with permission or game points.
This has been suggested and could be added though that is more UHCMeetup not UHC. FateMeetup already has a kit system and unless lots of people want it I would prefer to focus on more popular ideas.
This can be UHC. Take hypixel's hypixel UHC Champions gamemode, which is really fun.