Microctenopoma ansorgii FS

Tank looks great! Definitely plenty of space and cover. My opinion is that a pair or a group would do fine with the other fish mentioned. I have 6 adults, multiple males and females, in a 20g with lots of cover and have had no issues. The males color up and display to each other fairly often. I have only kept them as a pair when attempting to get them to spawn. And, out of an abundance of caution, removed the female as soon as it was clear the male was guarding his bubble nest.

I gotcha. And they seem as though they are between the sizes of the sparkling gourami and honey gourami. Does that sound right?

Most likely, yes.