The dwarf gourami is definitely good with the cards, and while I think it would probably not eat the micro rasbora, after thinking about it more I think they would be pretty darn scared of a fish that size. I'd either stick with the nano fish together or the larger fish together. Almost all nano fish are very timid and will do best if kept with other small fish. So if you do the cards I would pair with the dwarf gourami. If you do the micro rasbora I would pair with the trio of sparkling gourami (just be sure it's 1 male 2 females). The smaller fishes do have a lot more room to work with in a 10 so if you can get your hands on them, I highly recommend it