I finally made up my mind about a cichlid for this setup. This is what I'm going to use...
I can get these pretty soon from a local seller. It would have been fun to track down one of those more unusual species that occur in the papyrus habitats, but I think julies might be one of the most sensible options. The 'Pemba' type locality is especially attractive. I hope that they will be OK with the lampeye killis if I add the latter in a good-sized (~12 individuals) group.