Wow, great post! all of these tips are very true and very useful
I wouldn't just say that, I'd actually encourage people to do their own thing! there's this great freedom in webcomics compared to say, "mainstream" comics, in which you can do whatever you want even if it's something super niche and obscure. As a webcomic reader I really enjoy having this variety, so creators should use that to their advantage.
I'm kinda curious about this part, because when I joined Tapastic (around last August I think?) I'm pretty sure that self-promotion posts were not allowed? in any case yeah, self-promotion can be good but use it with moderation. Threads like "show us your comic!" are good, but making a new thread just to promote your comic is a bit too much for me, and personally I usually don't read them because they don't tell me much, just a link to a comic and that'd be it.
I think the forums are a great opportunity for artists to discuss and help eachother, so use that!! it's not just a forum to advertise comics, it's also to talk about comics themselves, art tools, techniques, ideas, et cetera. Make interesting conversations and you'll be getting a lot of interaction points with the community, which will also lead to more people seeing your comic.
Also: I think forum profiles and Tapastic profiles aren't linked? so you'd rather leave a link to your account and/or series somewhere in your forum profile in case anyone tries to look it up