This is a less than scientific or experienced review
I can't stand them! I can keep just about any freshwater fish alive but I've never had ADFs that lasted more than a few months. They were also never especially interesting to watch, although I imagine it may have been because they never seemed very healthy. I haven't felt the urge to keep them since the last failed attempt 5 or 6 years ago.
That's just my personal experience though. Lots of people enjoy them, so don't let me discourage you. They do make pretty good companions for bettas from what I've been told
Oh, and 1 betta and 6 neons is already a pretty full stock for a 10 gallon IMO
. I wouldn't add much more to it- maybe one or two frogs at most if you decide to go that way.