After Halo Reach gave us the ability to play as our own Spartan in the campaign, which was such a cool feature, would you have wished later entries did the same thing?
Absolutely! Even if it was an optional toggle for the Master Chief in a mainline campaign. It would add so much more replayability to the games. Heck! I still giggle at the funny armor combinations I come up with to watch in the Reach cutscenes.