I can't believe you're even considering that "entire arsenal" thing as a way to go. That would be a classic example of undoing a wonderfully good decision, and would be reason enough for me not to buy the game. When you said "What the two weapon limit did in the original Halo was to increase the complexity of encounters by making you pick up the weapons that you felt were optimal for each given area", you're missing a second and perhaps more important benefit. It also opened up the door to properly fluid combat. No ridiculous pausing the game to select from a menu of weapons, or tediously cycling through options. The simplicity of the two-weapon system is one thing Halo should keep, without question.

Not that I've played H4 much (in fact, I still didn't even bother to get my 360 fixed yet, so I've still only played the campaign twice), but I didn't object to any functional duplication of weapons, so I'm not really with you on that argument. Sure some things act similarly, but they still feel different. Also, it seems quite natural that each faction should have some functionally comparable weapons.

It's debatable to what degree they act similarly anyway, but I haven't played enough to be able to do more than raise the question really.