I try not to make unsolicited suggestions for what people stock (unless I see someone with an RTC in a 10G), but to be honest the first thing I thought when I saw your setup was 1.) man, that is a beautiful display! The second thought, was that the tank would look awesome with a school of Clown Loaches cruising along the bottom.
My only concern would be finding CLs large enough to end up off of your Aros lunch menu. I raised a baby aro along with some small CLs and the Aro's growth rate obviously outpaced the CLs and eventually the Aro tried picking them off.
But back to the purpose of the thread...I can understand the desire to maintain a biotope setup, but I stock first and foremost on ultimate fish size, then water parameters, temperament and typical water column swimming level considerations over geographic origin. Variety is the spice of life and that's why my tank is more of a melting pot than a strict biotope. I don't think I will ever have a tank without CLs because they add so much color and it's fun to watch how they interact...sort of like cichlids with their own little group hierarchy, but without the hyper aggressiveness (I should say usually...I had a CL that was the reincarnation of Adolf Hitler).
