Quake Live also has ~130 maps. Expecting people to learn map layouts for that many is insane. The upcoming Steam release will have Workshop support for maps, too, so that number will shoot up even more. We've also changed it since the initial release: it's now just 1 weapon + the regular machinegun, still limited ammo so you do have to move around the map a little bit, and grenades aren't even a choice anymore. There's definitely a lot of reason to pick SG or Plasma, so you mostly can't go wrong with whatever weapon you pick.
There's certainly a lot that can be said for loadouts in Quake Live gameplay wise, but we definitely noticed a difference in how much time a new player spent on the game when we released on Steam. It went up on average to not even a full match (<10 minutes) to about an hour with the Steam release. Still pretty low, but it's an old game that is still monstrously hard to learn.