Completely agree. Depending on the planet, or even how a specific game is going a player might take on a different role other than just killing but still be valuable to success.
For instance, some command posts require defense constantly just to keep them. Your kill numbers might be low, even your capturing CPs, but your value would still be worth some credit. For instance, keeping a vanguard inside of the Homestead on Tattoine who lays a mine at each entrance and keeps replacing them as they blow up is a sure fire way to guarantee success if you're playing alone against just AIs.....and it helps when you play online. But you get no CPs and few kills.
I saw a guy on last night, he was bragging that he had killed ''32'', however he had '18'' deaths. Not sure he had much value to be honest, and in fact, he lost that game. And he certainly should have been near the bottom of the list instead of at the top.
With spring break in full gear now, strategy is out the door and finding a good game of people who are playing with strategy as well as kills is hard to come by. I've pretty much given up playing online for the time being, why get frustrated with Halo2 rejects?