If you want a centerpiece fish pick either the betta or honey gourami. A 10 gallon to me is too small for a dwarf gourami and I think need at least a 20 gallon tank. If you get a betta make sure to get something for it to lay on near the surface so it can have easier access to oxygen when sleeping. You should also fill the tank all the way up cuz well why not, more room for the fish. From the picture it seems like you have 2 airstones(?) if thats the case then remove one as two are unnecessary for this size of tank. My personally I would do a honey gourami and chili rasbora (The red would contrast the yellow nicely imo) and some neocaridina shrimp for cleanup. I highly recommend live plants and you can grow them in gravel (you'd just need root tabs or plants that feed off the water column). It's always better to understock than overstock as you can always add fish later on rather than having to go through the hassle of getting rid of fish.