Oh and it would be cool for example if Artists would offer trading cards (limited set) who followers could trade or play with or whatever and you could buy them with these points.

It would also support artists that aren't not so known when they offer cards you can achieve and then trade with others.

Random 5~ish? Minutes of fame for Artists that fulfill a certain rule-set for example:

- has posted at least 5 new pieces of artwork in the last 10 days

- has less than X amount of followers

- is on the site for a certain amount of time

- has a high promotion / fav per view ratio

People could vote for him to be featured, then he gets asked when a certain threshold is filled if he/she wants to participate.

Or a trending section where art that has a high view to fav/promote ratio will be shown.

I guess there are some algorithms that would try as best to promote "promoteworthy" artists while involving the human factor.

Besides that, you could somehow encourage popular artists to promote aspiring artists.

Maybe the site needs something like a virtual currency / point system to make it attractive, i don't know.

Yes please. The focus is way too much on popularity than diversity. Aspiring artists should be (extra?) supported if they want to.

There could also be competitions among Artists with a specific watcher range or up to a certain limit to gain view.

Or if you followed an Artists it could show you artists that could also be of interest based on the tags an artists uses on his items (not all of them but the most used one expect common ones like "male, female, colored" and so on.