From my point of view, I've only ever given favourites if I felt the artist or author deserved it, as a recognition of their work and effort, which is where my enthusiasm for the Promotion function comes moreso. Rarely do I go back through what I've faved.
I can see how Collections could come in handy for people who need it, particularly if you're an artist that mainly deals with non-adult specific work and don't want your fan base to know what kind of perverted stuff you secretly enjoy (I've never had issues from stalkers or anything like that, but for big name artists I can see the need for this).
I feel this also applies to by extension the difference between favourites and promotions, which should be updated as well.
From looking at Varka's comment, it looks like they're addressing it. However, I don't believe a friend system is necessary. If privacy settings can cover this than I'm all for it.
No point in really hiding favourites, in my opinion. If they ran the favourite system like most other platforms, and then used the promote system almost as a share tool, it would work much better.
Make it so that when you favourite something, it get's added to your list of favourites. People who received the favourite get notified by who it's from. That's it. No posts on their page saying "this person favourited this" etc. If people are precious about hiding this however, perhaps have a preference setting that makes them private, in which case only the user can see what they favourite, and the person receiving it gets notified that "someone" has favourited it.
When promoting something, make it separate from favourites. When you promote, it publishes on your timeline that you have "promoted" said piece of work, and maybe even publish in people's notifications. Say if you are following someone and they promote an artwork, it turns up in your feed under a separate tab specially for promotes.
That is a much more efficient way of sharing work that you like and give exposure to the artist/author.
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