Hey! I was part of a forum called Artplay once, it was super fun! The place is closed right now though. But here is an example of one that lasted pretty long.
artplay.boards.net: Thunderstorm | ArtPlay
There were a lot of characters, some ended up leaving. Some new people joined. I mean, people are busy and life happens. It's hard enough to keep up with type-based RP you you can imagine ART-based RP. But still, it was super fun while it lasted.
Sometimes the art was nice and in full color, sometimes it was just rough sketches with mostly text.
I guess it depends on you. If you don't mind the story being really stretched out, it's not too bad! My friend and I got pretty far in a 1x1 RP:
artplay.boards.net: [one x one] Broken Chains | ArtPlay
Even if it took over a month to post, we would try to be understandable.
But anyway, I think there is a website dedicated to this very idea now! I will have to look for it again. The person who created the forum found it, actually. XD So I'll link it once I find it.
SO also. I'd be very interested in giving this a try with you, if we can find some agreement on what to RP. ^^ Let me know.