Why would you not implement a more customisable multiplayer?
For an example, Serious Sam (the original ones, not HD) contains many many options to customize the gaming experience.
Well of course, you could hide the selections behind a "Advanced option" tab, so that players could still choose the normal "'are you braindead', 'booring', 'normal', 'now we get somewhere' and 'serious challenge'" predetermined gaming experiences.
What I am trying to say, let your gamers choose more and don't be stupid as another 'big boy' on the playground.
And, please, don't go the long way to utterly balance the game to death.. That sucks, too..
I believe in replayability coming from the choices we all do differently. So, please, put that advanced options tab there ?
I mean, if I want to play some survival mode game, why not in Torchlight II ?
I kinda liked Magicka, but, ..
I loved Warhammer 40000 Space Marine, oh that stomping grinding multiplayer fun, but .. why only 4 player co-op ?
Borderlands.. mmm.. sweet.. but, 4 player co-op?
Why not go all the way if your engine can handle it? Opt for 8 or 16 player co-op ? You see, we all love the smell of napalm in the sunrise.. Put in some more random spawns, scale the world harder.. Whatever.. Don't stop, walk the extra mile, please please ?