some other random ideas:
pony imageboards:
bronibooru.com
twentypercentcooler.net
pbooru.com -> old Ponibooru repository, NSFW ad alert.
own blog:
tumblr.com -> make an account, follow some people so that they’ll follow you back (this is essentially a webring, you bring visitors to each other’s pages), link from your DA or DB and you’re golden.
DeviantArt alternatives & other:
elfwood.com -> fantasy themed
epilogue.net, artrift.com -> never heard of them or used them, just saw the links somewhere
Newgrounds art section
reddit.com/r/Art
conceptart.org -> for more serious/pro critique
cgsociety.org -> for CGI pros
Sheezyart has been “under reconstruction” for over a year, and it’s doubtful if it will return.