I've had a hard time evaluating Reach's multiplayer, in part because there are so many polarizing elements to it for me. The DMR gun play is godly, while armor lock is the single worst thing to happen to Halo's combat. But over the past few days I think I've settled on a general take on the multiplayer.
Basically, I think it's a good time when there's a ton of crazy stuff in the mix and lots of players, as in Multi Team. The big mix of weapons and Armor Abilities combined with lots of players makes for a fast, crazy game where there are a lot of moving parts but none of them dominating the other. Even in bad games, I consistently have a good time in it.
On the other end of the spectrum are pared-down game types like Slayer Pro or Slayer DMRs, or Arena. And those games are pretty fantastic as well. As I said the DMR gunplay is great, and the AA sandbox is stripped back to focus on mobility, and that slimmed down sandbox clicks perfectly.
But in the middle, between those two poles, is what I don't like. 4 v 4 Slayer with Armor Lock and jetpacks and grenade spam galore is very unpleasant. Unlike the ends of the spectrum, every other death can feel cheap or arbitrary or unfair (all at once!). I won't belabor it, but Armor Lock is truly a gameplay disaster, and it's only in the chaos of Multi Team that it gets overwhelmed to the point where I can avoid it for the most part.
What's odd is that with Halo 3 I was of the opposite sentiment. I strongly disliked crowded game types and chaos such as Heavies, and detested BR-only starts and MLG-like settings. I quit many a customs night because of BR-only radarless games. The middle, default-type settings are where I liked to stay, as I felt the sandbox was balanced perfectly. But with Reach, I find myself avoiding the vanilla offerings an steering toward the all-or-nothing playlists.
One thing I'd like to emphasize is that I wish Bungie would craft the load outs more carefully for each map. Rather than define load outs by game type (Slayer, Slayer DMRs, etc.) they should be defined by game type and map. Jetpack, for instance, does not need to be on every map. Some maps simply play better without it (Reflection, I'm looking at you.)
And on that note, not every game type is suited to the default map layouts. For example, the sniper rifle should not be on Asylum Multi Team Crazy King. Every time that comes up, there's a dude ignoring the gametype and just camping the hills with it for kills.
In general I wish the overall sandbox were crafted more carefully for each game type and map combination. Because with so many variables at play in Reach, there are many more combinations that simply don't work than there were in Halo 3. And the way its set up right now, the default map is used with a fixed set of load outs across most game types - and that just does not work. Reach's multiplayer can be incredible, but I've already seen more truly terrible map/game type combinations so far in Reach that I did in Halo 3's entire run. Much of it has improved with each playlist update, but it's got a long ways to go, IMO.
But I am glad to have found a few niches in the MP game I do enjoy. I fled Firefight's Rocketfight-dominated playlist back to MP, and it took me a while to find a few offerings I enjoyed. But at least there are some - for the first three months the game was out, I didn't think there would be.