The DM doesn't have to cope. The players do! (^_^)
I have to agree with Imp. If you are lucky enough to have such a cool combo--that could have some really interesting adventures--I think it'd be a huge mistake to try to outfit them with NPCs to fit them into that standard 6-PC model of yours.
Imp said:Wait, you've got two PCs, a rogue and a monk, right?
That's a pretty awesome stealth tag team and you should orient at least some adventures to play off of that. They wouldn't necessarily seek out the kinds of things a 4-slot standard party would look for all the time.
I have to agree with Imp. If you are lucky enough to have such a cool combo--that could have some really interesting adventures--I think it'd be a huge mistake to try to outfit them with NPCs to fit them into that standard 6-PC model of yours.