Most BF4 patching is done server side, even a lot of stuff that was traditionally done with a client patch, hence 2 client patches, 12 server patches.
As for the expansion only played a few rounds but the maps have a nice variety and seemed to play out quite well and a couple are properly pretty, guillin(sp?) especially. The guns are a good selection and all worth using. MP7 and MTAR are beastly up close, solid challengers for the P90 and ACW respectively. L96 is another sniper rifle, not much to say. L85 looks interesting, might lure some away from the ACE for close in, going to depend on the recoil, pain to unlock though.
Gadgets are pretty meh, UCAV looks like yet another entertaining way to troll roof campers.
Being basically just a diet TV missile for support, but
tbh I can't see it ever edging out my C4. The other one, SUAV I think is just a fast MAV.
Bombers seem pretty underwhelming so far, was expecting something with a bit more shock and awe.