New answers tagged editor
I would honestly build the least amount possible, release it and wait for people to ask for more features. Start with allowing simple text input and auto-linking urls. Autolinking can make it easy to spam your forum though, so watch out.
I'd put in a small button that shows (expands) / hides (collapses) the more advanced Stack-Exchange-style features. It's convenient to access, but doesn't clutter anything if the user doesn't want or need it.
Top 50 recent answers are included