I'm C2 (C1? I forget where I finished today) now and enjoying it. It's good to see some folks giving various weapons and PAs broadly the same assessment as me.
I am surprised people are rating Ride Slash highly. It seems to be the weakest of the three sword PAs and if it goes up against either of the others it will lose, regardless of pings involved.
I've had a couple really good runs with Rifle's Piercing Round too. Its purpose is not to kill, but to ding multiple enemies in a group and basically doom them. I've managed to set up a couple awesome team sweeps that way. Sure it doesn't get you emblems or battle points, but it helps win games.
I've had one or two instances where I've hit an enemy who has taken damage but not died, before they hit me with exactly the same weapon and I have in one hit. It's... baffling, but fortunately doesn't happen that often. I can only imagine there's some damage variance in the attacks, perhaps as a balacing mechanism?
What does happen often is lag. From the UK I am at a definite and permanent disadvantage; multiple times I've ambushed people around corners only to die to them because the game apparently communicates my position faster than my attacks. I've also escaped to safety only to die behind walls a bunch of times. These are a frustration for sure, but I don't know what can really be done about it.
I think it's related that no weapon gets Sidestep Jump. Mobility in battle arena is really awful and as a jet boots main it felt painfully slow at first. But if everyone could zip around the ping issues would be way worse, so I've come around to that as a necessity and got myself used to the slower pace.
The most annoying thing of all for me? Whenever I'm on a losing side that's being slaughtered, I'm usually in the top 3. It's not even that it feels like it's not my fault we're losing. It's more that since I am in the top 3 I can't sneak around and assassinate the other team's effective players. I like the mechanic of giving that advantage to the bottom 3 though, so hopefully in a week or two the people who are will have learned how to take advantage of it and games may become more balanced than they typically are now.
It amuses me that people haven't really mentioned skills in this topic. I think they can be unbalanced at times; Protect used right can seriously be a tide-turner. None of the others can do so much with lag involved.