Stocking Advice? Can I Put Small Gouramis With My Large One?

[tyedyefishy]

I have a fully grown male 3 spot gourami that is definitely a good 4 inches. I really want to get him two (three maybe?) lady friends =). He's very peaceful and has a great temperament but I'm wondering if it'll be a problem to put two females that are only maybe two inches. If it is okay to get some females... is it pretty easy to tell the difference in sex that young? I'm really interested in the opaline and the gold gourami colors.
and a little stocking advice on the loaches and rosys please?

I have a 125 gallon (473L) tank with
One fully grown 3 spot gourami
10 medium sized long finned rosy barbs
5 angelicus loaches
and 1 dwarf albino bristlenose pleco