I guess I would call it a center piece fish sort off. I just want to add 3 or 4 more fish that get to be about 4" long, get along well with my other fish. My tank is fairly open. Was looking at some videos of some Keyholes. They do look pretty cool.
EBAs may eat danios though. They can fit rummynose in their mouths, and danios aren't that much bigger. Keyholes won't eat danios though. There are other dwarf cichlids and some gouramis that would work too, though.
Not really, maybe a tad bit longer. And even buying young EBA won't solve the problem long term - they do grow, and fish will often eat other fish if they can fit it in their mouths, regardless of having grown up with them. I wouldn't risk it, personally.