A few years from now nothing you do in this game will have mattered. Your rank, kill/death ratio, win/loss ratio, will get you no where. So, if your going to play the game, do it for the enjoyment.
Idk, but I'm not a huge fan of the Brutes or pretty much anything they brought to the game. I'm glad we'll get to fight against the Elites again, pure Halo.
Besides...
Spectre > Prowler
Chopper... meh, we did fine without it
Brute Shot, not a huge fan.
Spikers, well no one really uses them anyway (go ahead argue me)
I think if anything Reach will bring back a bit of a classic Halo feel (with a few twists of course)