Actually, learning HTML will be of utterly no use, because you can't include HTML in your posts. Look down the bottom left of the thread - "HTML is Off". You might want to learn BBCode and some of MW's fancy functions, but there's buttons for the lot of them, if you wish.
RPOL's post-as-character system isn't in place here. I think - and I'm not 100% sure, so don't take my word as gospel here - that this is a deliberate thing. People post as themselves, so that you know who you're gaming with. You can get an idea of who someone is, it's more of a community.
But, again, I've not been on RPOL for longer than a cursory glance, and I can't recall where I got this idea from. It may have even been another PbP site.
Give MW a shot. Worse case scenario? You're running one game with inferior tools. Best case scenario? You're running multiple games with superior tools. What have you got to lose here?