My first impressions are as follows.

-I am a pretty hardcore player of destiny, and it is an absolute breath of fresh air to play a game of pvp and not be close quarter shotgunned at every turn. This game rewards a more skilled hand and I was able to jump straight to a high KD ratio right off the bat, which was a good feeling.
-It IS extremely hard to tell where you are getting shot from. Basically if you get caught in someone's sights and you don't immediately see them then you're smurfed. You'll be whipping your sights around while your health is quickly melted down and you eventually die. I don't really mind this because it promotes sticking to the trenches that are available to you. This game truly feels like a war more than a deathmatch.
-Sniper rifles on a cooldown, I love you. I'm not sure if that system will stay that way once everyone is level 5000 or whatever, but at the moment that is an awesome way to make sure that no one can just camp those massive open maps and mow everyone down (I tried doing this and though I had a good KD, I got significantly less kills as when I wasn't sniping). Add to this that the sniper rifle scopes don't have a very crazy zoom and you're left with a game that promotes moving your way carefully up the map so you can get kills with your primary weapon.
-STAR WARS! Music, atmosphere, soundeffects, holy smurfing balls stay away from me Darth Vader you dirty bastard, all these things are spot on. I love that universe and this plops you right into the thick of it.
-Despite all the good things I've just listed... it's kinda boring. But I'm 90% sure this is just BETA limitations, because 2 maps over two game modes is never going to be the most varied experience. On top of that I've not been able to spawn as Luke or Vader yet and I've never found myself inside an AT-AT or a TIE fighter, so it's just been shooting for me so far.

I think the full game will be a much grander experience, but the gameplay and atmosphere has laid the groundwork for this game to be extremely epic.