I'm really new, too... so my advice only goes so far... But! I'll give it a shot.
I've not yet entered the world of outside social media, but the past few days I have been spending a lot more time on the Etsy forums and teams, and this has really increased my views and favorites... its been really encouraging! Especially wonderful are the team threads where you pick an item from the shop above you, favorite it, and post it in the thread.... this helps get everyone involved more exposure....
I hope my little bit of advice will help! (Also, personally, for the sake of organization, I think the bulk listing of shirts thing that you're doing is very good!).
