I think the current leveling system is just there for 1) Casual players 2) Tiding over the hardcore players until the release of their skill-based ranking system coming early 2013 You are correct that many players will be reaching their level limit by the turn of the new year, which is exactly what I speculate that 343 wanted to happen. Something to buy them time. If you haven't noticed, the win *insert gametype here* commendations are ridiculously high in comparison to other commendations. I believe this is due to their coming release of visible, trueskill ranks. I can continue on my speculations, but fact is, they are releasing a skill based ranking system. http://blogs.halowaypoint.com/post/2012/11/02/Halo-4-Competitive-Skill-Rank-Announcement.aspx
Sadly this would be a good thing but the ranks are only visible via Waypoint. Check the 343 forums for source. Sucks, I know.
I would like to see load outs for spartan ops and war games be separate so that I can personalize my spartan ops spartan loadouts more. Like if a group of friends get together one person says ill play sniper and another says they want to be the heavy gunner. The sniper can take a sniper rifle and a backup weapon and the heavy gunner could grab a saw. The specializations could reflect this. You'd have to limit the power weapons though. Like if you take a power weapon then you can only have a pistol type weapon unless your specialization lets you carry a bigger weapon. Lots they could do for it.
You're probably right. If Tali, Garrus, and Liara aren't loyal by now, I'm gonna throw them out in space.