I usually play on the same few servers, and rarely do I get on a shitty server even when searching randomly through the list. Of course I've logged over 150 hours (my account says over 250 but my friend always leaves it on the title screen when he's done and it logs time until the comp goes to sleep lol) so maybe I've developed the ability to subconsciously spot bad servers.
My friend seems to have more trouble with this.
But the server browser itself could use some help. They should just use the one built into Steam, it's way better and easier to find friends.
As for unlocks, I earned them all early in my career, around level 20 I think. I found it fun to move up in the ranks and earn different equipment. And the starter weapons are not exactly crappy, I see level 50s using them all the time.
It is stupid that you have to unlock things like the medpack for the medic, but again that happens so early that it's not a big deal at all.
One feature request I have: a dedicated "thank you" button. A little courtesy can go a long way, but it's takes too long to type that out in the middle of a fight.