You could do the pearls with a nice size school of rasboras then some smaller loaches to inhabit the bottom like Kuhli loaches. Then you're getting fish all from the same region and those Pearls will really stand out as the center piece.
It's true that the khulies could be a nice idea!
That was exactly what I was implying when I said pick a bottomdweller from Asia. Besides Kuhlis, Chain loaches (Ambastaia sidthimunki) would also be a nice option. But then there is definitely no room for cichlids anymore. I would really leave them out then.
Or the middle way of Honey Gourami. But I think the OP is definitely set on the pearls.Personally I would drop the pearl gourami and go with sparkling gourami. Things just work out better with small fishes.