I don't know if it's strictly possible but it would be excellent if there was an option to integrate with the most popular streaming services (twitch, picarto, tigerdile, etc.) that automatically detected when your linked account was streaming and displayed it as a list of users currently streaming.

I'm familiar with Pixiv's image response feature and almost suggested it, but I figured more folks would be familiar with the Tumblr example. :D

You could also have ebay-style sorting options when browsing auctions, like sort by ending soonest, or auctions with autobuy/buy-it-now only.

Support for multiple contributors to a series would also be a lot of fun. On tumblr you'll often see artists reblogging each other's art with new drawings in response and it turns into this sort of participatory comic.

Sure, but having a site dedicated to being an art showcase does no good when the only way to prevent contact with harassers is to just opt out of using the site completely. Right now the only place I feel comfortable posting some of the content that I draw is to a private twitter account. Furrynetwork currently has no accomodation for that sort of use case.

I think 'fresh' is just another word for 'sort all by date', and displays all of the submissions featuring that tag in order from newest to oldest. But other sorting options would be handy, like sort by submission title or sort by artist.

Yeah content filtering to specific user-defined friend/follower groups would be huge. I don't want everything I post to be publicly visible.