The various rows and tabs being slow is something we're definitely aware of. A lot of systems in VRChat were designed with "hundreds" of users in mind, rather than "thousands". As a result, performance degrades, and you get menus that don't respond as quickly as you'd like.
A "refresh" button unfortunately would only address this issue with a band-aid, and probably one that doesn't truly solve the issue.
In order for us to solve these issues, major backend changes have to take place. We're working on it, but it takes time.