Hello, everyone! I'm brand new to the ANA forums and website in general (either this new and improved version or the older version), but I'm pretty active on other numismatic forums (and a bunch of non-numismatic forums). I do have a suggestion or two that I didn't see covered here. :)
2) A built in selection of silly emoticons ("smiley faces") and/or a list of commands one can type like ":grin;" to display an emoticon. It probably sounds silly, but a few little smiley faces here and there can really add a lot to a post. :)
The only other thing that I personally like on other forums that is probably not a "relatively quick and painless change" is the ability to like a post, in the same way that one likes a Facebook post. It'd be nice, but I won't hold my breath for that one!
In general, it's looking good! :)