So, without further ado:
-One of my bigger issues is with the health meter. I think players would know that the top-left bar was the health bar, and it kinda bugs me to see the bar go opaque every three seconds to constantly remind the player that it was a monitor of their health. In addition, I found the narrower segments of the health bar a pretty neat feature, and the icons under each one informing you how you received that segment was cool too, but do they really have to be under the segments and not an integral part of them?
However, this is just me being really nitpicky. I honestly care more about balancing than minor issues such as this.
-Which brings me to a more major problem: reloading speed. You'd think that a drum magazine would be really hefty, but it never actually seemed to impact the running speed of the characters, and the draw speeds of guns equipped with drum magazines were still too fast. To make things worse, the reloading speed of a gun with a drum magazine does not change whatsoever. I found it frustrating when I saw a video of a Tampa equipped with a drum magazine, and it was reloaded just as fast as a Tampa with a stock magazine. It puts players without an enhanced magazine at a disadvantage because they will have to reload more often, and if there's no benefit to having a gun with a stock magazine, then everyone might as well equip the biggest magazines possible because there's no performance degradation.
-I wonder how the Weapon Select is supposed to work. Do you just activate it in the Command Post and it will list you all of the weapons you can switch to? Or will it give you some recommended weapons and correspond a button to them so that you don't have to scroll through a massive list?
-They fixed the "glove doesn't change unless a class-specific item is used" glitch. I remember with the PAX 10 Walkthrough of Container City, Jolly changed to a Soldier, but his Engineer gloves still stayed until he planted the HE Charge.
-I've already said this in a previous thread, but the crosshair circle rotating while you reload is a nice addition. It'd be cooler IMO, though, if the crosshair turned somewhat opaque, and it filled from the bottom up with white as the reloading sequence neared completion.
-Another thing I've recently noticed: In a vid from PAX East, after you finished disguising, the player you disguised as would flail about randomly and disappear in perhaps the weirdest way possible. Personally, it would be cool if the corpse was replaced with your character as you disguised, so that no one gets suspicious. If that's not possible, however, ET:QW's way of handling disguises wasn't that bad (the character would just disappear with pixels eating away at them, or something liked that).
That's all I can think of right now. I'll edit this post later when I have more observations. Any comments?