Not being able to go into cover when an immobilize effect should get a fix, because you're a living target for jet chargers/leapers, which irritates alot.
Found it in the beta and it's a great source of annoyance and outright stupid, i've mentioned it atleast 3 times in the Agent/smuggler forums but it seems to fall in deaf ears.
As for Marksman tree (i'm an agent) has the lowest viability in PvP because it's build around the cover system.
I'm currently letha specced because it fits me much better and i actually can kill those pesky melee'ers now .
As for operatives, i have a 360 vision, get first hit to get them out of stealth and they are frustrated
And a few posts back, getting 400k dmg is pretty much doing dmg only and not helping your team, you contribute nothing.
200/300k is far more reasonable as top dmg. (can do better or worse depending on amount of harrassment)