I find that the only reason someone would go for melee is to artificially inrease difficulty. So much for diversity.
Or, role-playing. Just saying.
*GASP* Who would have thought that! That's why I did it.
In general the versatility of ranged characters is a bonus in pretty much any setting. Even in something like Defender's Quest (the tower defense RPG) I focus on ranged units.
I'm surprised no one mentioned how Friendly Fire is a non-issue with a team-comp of all ranged characters. That's the chief reason in NWN2, and Dragon Age: Origins I made sure I had a party of ranged characters.
I don't think friendly fire is a big issue in D:OS. Only few spells have area effects anyway and you can in most cases position your melee fighter pretty well to avoid friendly fire.
