Have a "highlight reel" tab on profile. Didn't X provide this feature to premium users a while ago? I think it's a great feature.

I'd like people to be able to see a list of the substantive posts I've made with the shorter and more insignificant posts filtered out. (let the account owner do the filtering. perhaps have a post or comment not appear in this list as a default but when the user does a write-up or some writes some thoughtful comment he can toggle something or somehow mark it for inclusion in the highlight reel section) Right now I can go see the past posts of an account but there will be lots of noise.

I'd use the tab and populate it with more ever-green and self-explanatory comments of mine that stand on their own. When people go over my history they'll have to sift through lots of stuff that is likely a waste of time to them (and to myself quite frankly lots of the stuff) and they may bail before getting to posts that might have actually been worth their time and been useful to them.

When visiting a profile I'd like to be able to get to know the entity behind it more efficiently than I can now. A good way to achieve this would be to have this kind of tab I speak of. The profile description could be used to list these but I think having a separate tab for a curated / filtered list of comments would be better.

Also always welcome in my book: more fine-grained and more flexible search and sort options.