BF1 is a really good game, however if you can get into a really good position on top of a building or in cover from all the vehicles as the sniper class then you are pretty much invincible with a friend as a medic nearby, I've gone about 20 - 1 in some games using this tactic, so yeah some balance issues, but overall it is just a beta and in the future it will improve, cant wait to see what they come out with for the full version!