I focussed since the beginning of this year selling paintings only on eBay, Vinterieur, 1stdib and panomo.. Mostly paintings AFTER well known artists or limited edition prints. Since I have this know-how and know how to change the title and description, I had to cooperate with someone in this field, but I only sell on the platforms above only where they only sell Furniture mostly. And of course eBay as well. And of course I also sell on plazzart, selency and etsy too. but only make 25-50$ profits after taxes ... which I don't want to focus anymore. Since I want to grow further... And to make it short, I really don't know, if I also have to go on "ETSY, Plazzart and selency where I would only be able to make profits like 25-60$" because on the Furniture sites, I make 100 - 400 $ in profit. A premier in appearance online & selling to cheaper customers? Thank you in advance for the answer and thoughts..
Are you also managing own website along with listing on these portal?? You are selling painting means you have enough number of unique image ..... There are many platforms like 500px who can drive good amount of related traffics. You can drive traffic to your website (If managing) or to any portal like ebay (Your store URL).
A mainstream/broader approach seems less risky to me, I would go for that one. You can still grow, by focusing on a good marketing strategy.
It's also worth considering the time and resources required to manage multiple platforms. If you are already struggling to keep up with the demands of your current sales channels, then adding more may not be the best decision. Overall, it's important to weigh the potential benefits and drawbacks of expanding your selling channels and determine if it aligns with your overall business goals.