If all the fish get along is the main thing IMO. I don't think your nearly overstocked. A lot of your fish are bottom dwellers. Tiger Barbs are notorious fin nippers but if your not having problems with them then wouldn't worry about them.
^that's the other comment I was waiting for, te tiger barbs. Every once a in a while they'll have a fight amongst themselves for pecking order, but I've never really seen them nip at anything else. Keeping them in a large group I think is the key here. Probably also helps that there's nothing in the tank they can pick on without some serious repercussions.