First of all, I am by no means a hardcore PvPer, only do some Frontlines occasionally.
But by now I have see three things happen over and over... to a degree that turns me away from PvP entirely.
a) Extremely unskilled players end up in the same party and instance as extremely skilled players, turning the first into cannon fodder for enemy teams, which is a giant frustration if you are lumped in a party/alliance with a lot of the cannon fodder, but also not great for those who are nothing but just... fodder.
b) Party/alliance composition, oh how we are in RNGsus hands. If you end up in a PUG party where no one has healers leveled sufficiently? While the other teams have enough healers to keep them up? You are dead dead dead, prepare for 3rd place as you get slaughtered. Your own skills, team coordination mean little to NOTHING then.
c) Can we talk about the elephant in the room, premades? If I see a premade mowing across the map of Frontlines, slaughtering and bullying naturally less-coordinated (and usually less skilled) PUGs like a well oiled machine, that is not decent, fair PvP...
... that is a nasty slaughter-fest creating more frustration for all but the handful of premades out there who feed on all the other PvPers and laugh their heads off about this near-exploit in the system for easy victories. And yes, in my experience it is rare to the extreme to see more than one premade on a map, IMO it really borders on an exploit (even if not against ToS of course) how they mostly seem to queue during times when it is 8v8v8, where they know they will reign supreme.
All of that together has turned Frontlines into something nasty, ugly, and sucking out whatever fun was once in there. No one would cheer if highly trained knights or samurai of a well-disciplined and experienced, tight-knit unit are given a permanent opportunity to slaughter feebly experienced, randomly thrown together peasants for gain and glory (is that actually glory?), but that is what it looks like by now when you allow experienced premades into PUG maps.
I just came out of such an instance, where we PUGs could just give the one premade a wide berth, while they chased and bullied us across the map, and most of my party members shared the same sentiment here:
Don't allow premades onto the same maps as PUGs. Either you get a map only of premades, or only of PUGs, no mix-matching.
And I say this as someone who likes to queue with friends, including into PvP, but I rather give up that, than seeing the current state continue.
Also please at least TRY to rank people according to PvP skill and through it form according parties and maps so people can learn at their own skill level and get better (rather than get conditioned to be nothing but canon fodder, going in only for the 3rd place participation reward) -- because it is obvious that right now that is not happening, going by the results.
And don't allow parties to happen without anyone queued in as a healer, to at least a little bit alleviate the "Oh joy we have zero healers, we are so dead."
Of course you can now say, "Well if you don't like it then don't do PvP." And if things don't change that's what I am gonna do. But I still care enough to point out that by this kind of logic the quality of all content can be allowed to slowly degenerate if there are flaws in the system, until it becomes near-dead content, or in the case of PvP either something done only by premades and newbies who leave after a couple of frustrating experiences, or only participate for the 3rd place wolfmarks, and don't give a hoot about the quality of the match. Is that what we want here...?
(And yes, I have seen plenty of comments in Frontlines by now of people saying essentially "I don't care, win or lose, I get my participation reward, screw PvP, I just want the glam/hairstyle/minion/whatever." Baaaad indicator of where Frontlines is headed these days...)