For me it would have to be serpae tetras - great orange / pink colouring and nice black&white fin details.
They shoal quite well together but as for the tiger barbs may nip at other long finned fish. I have 8 and they are constantly on the move, either shoaling or trying to establish who is top dog - they chase each other around tirelessly. Keep them in groups of 6 or more and the aggression is kept between themselves.