Hmm, with Neets I found that there is a lot of trial and error to find what works. Some individual Neets seem to be so much more aggressive than others. I actually had a pretty outgoing Neet in with a similar sized 5 Star (Hemichromis elongatus) about 15 years ago, and it was no contest. The Neet tried to defend it's turf, but the elongatus pretty much easily defeated it. That was one bad elongatus though. I had him in a tank with some nasty mbunas, and he shocked me by defeating the king of the tank, a medium sized chipokae. That's the first and only time I've ever seen a non mbuna cichlid outduel an aggressive mbuna of the same size on equal ground. I know regular jewel cichlids usally get their butts kicked by equal sized mbunas.
So far my experience with Neets leads me to think that on the whole, they are aggressive, but not hyper aggressive for the most part. I do have one that is brutal, he was a WC from Rapps, along with 4 others, and he just brutalized them into total submission, killing 3 of them. I could see he was much more interested in killing than breeding, so I moved the other Neet and he is doing fine.
I recently got 8 tiny Neets from TUIC, they are an inch long in a 30L with 4 New Guinea Rainbows twice their size. They'll grow out in there for now until I move them again, I hope to get a breeding pair. I've never bred these before, it would be cool to get a pair.