I do graphics for my quotes, but it is a very slow process and I feel it's a dead end.
Hiring an artist for a free novel... writers are already the bottom of the barrel in terms of engaging interest vs time spent--on this site only 90 or so free novels crossed 1K subscribers. And everyone wants to charge us ... vanity press, editors, cover-design, character art, moodboards, promo artists...
Do I have to pay a few hundred bucks when I see people with beautiful covers not getting views?
When not a single picture-quote of mine got external like outside friends I made on the forums?
When two polished and illustrated flashfictions got like 2-3 likes?
I think people who do well on social media are people who reach out to other people's emotions with the means that are natural to them, like speaking to a cause or to a group or just spinning out something completely normal in some fortuitous way, like pictures of their cats or they have a beginner boost like being connected to an already popular fandom or a cool job...
So, i kindda feel that a small amount of popularity and friend building needs to happen before the success on SM. Like you need a core of friends or followers to start growing it out--unless you can adhere to an already supportive group that actively seeks out and fosters their own.
Network, stick together with those who would prop you up, support them relentlessly and pray for at least a small hit on one of your stories... I don't think there is another way into the SM's good graces.