Can you back that up with some examples? When I read the question I initially assumed there would be loads too, but if the essential elements are taken as:
- a group of people
- aspiring to be heroes but initially unknown
- exceptional and complementary skills
...then there aren't as many as you'd think. My own Norse example (up there ^ somewhere) actually falls down completely on #2 now I think about it (by any standard, Loki and Thor were already famous) and barely passes #1...
Actually, Tolkein's Fellowship misses on #2 a well. All of the non-hobbit members were well known in their spheres of influence, and most were acknowledged as powerful/heroic (with the possible exception of Gimli, who seems to be a prototypical dwarf prince, and fairly young to boot).
I don't think the conceit requires #2, and you'll get better/truer results if you drop it.