The most important things which keep me coming back to a forum like this are community, layout and, let's be honest, opportunity to find more players to my games. To my eyes layout, after a couple UI tweaks, will be just perfect here. It's clean, it's tidy, it's content-oriented. The community so far looks great (I have a feeling that itch.io crowd is a bit more mature, but don't prove me wrong here) and after a while it'll come down to mods/reports/rules and having fitting sections. As far as self-promo goes, it's nice to see devlog and release sections already, having weekly threads will help too.
Now a couple of ideas I'd like to reiterate or suggest:
- weekly feedback/screenshot events (like /r/gamedev does)
- a section for youtubers (gamedev videos, indie letsplays) to keep their "youtublogs" (let's heat up that gamedev + youtuber relationship we all benefit from)
- a section for distribution/publishing/promotion related discussions
- off topic section, maybe forum games too. I'm not a huge fan of those, but many people are
- tutorial/article/blog section as Median suggested (nicely tagged or grouped by the category)
- stricter rules for posts in self-promo sections to keep them less spammy (one post per game, must include screenshots)
Also, this might sound crazy and could go wrong in many ways, but what about embedding itch.io games in your posts? I think it would be pretty sweet.
Other madness would be to have an on-demand private forum section for your game, which some of the bigger/complex/multiplayer projects could benefit from, but it would cause an influx of "empty" non-dev accounts, which might not be a good thing depending on direction itch.io is moving.
So here's that for now. Let me know what you think!