My single player Op4 campaign (tentatively titled "Op4: Wrench/Barnacle/Snipe") emphasizes use of just the wrench for most of it, then the grapple, and finally the sniper rifle.
Do people generally hate that? The problem I face is that, for people who love the wrench (like me), it's extremely easy to clear rooms of monsters. For people who hate melee, it will be super difficult.