Well, some cichlids that will breed in a 10g are apistos, rams, or tanganykan shell dwellers, or kribs.
It's possible to breed convicts, but they must be small. I really want to get a couple of small cons to breed in my 10g, but I think 10g is just too small for them.
in my 10 gallon I have one bolivian ram, one green terror (growout duh), and 2 african butterfly cichlids.
Butterflies are the absolute most aggressive dwarf cichlids I have ever had. I had a 29 with all dwarf cichlids and the butterflies killed each other at the drop of a hat. The one I have now is the boss of the 10 and the green terror is the lowest on the pecking order (and all are the same size).
So my vote is for bolivian rams, hardier than blue rams, but a little larger. And they are a little less colorful, but I mean much hardier and tolerant of high pH and hardness. You pretty much have to have an RO unit if you don't have naturally soft water and want to keep rams.
you could check ot the aeq. curviceps. I have kept and bred these fish in 10g aquariums. They are quite peaceful fish that didnt seem too interested in any of their tankmates.