I wanted to chip in here, I main a zerker only because I love duel wielding 2 weapons (PKs actually use a 1hand sword and a dagger which I would exclude as its not same weapons).
I love the zerker, I honestly do not care if it is OP or weak compared to other heroes, nor do I care if its the most popular or not. It's just the way he holds those 2 axes appeal to me, loving it!
As for me, I do win on most fights just because I use every tool it has (feints, parries and most of all deflects).
I feel zerker shines out on its deflects which follows up to an un-counterable guardbreak which then = to a free side heavy attack.
As for its infinite chain, lets be honest. People now will say its OP as its fast for now, but when the game matures enough and players get more experienced, those infinite chains will just be something in the past.
I hardly continue my chain up to 3 or more attacks as I try to feint it and chain directions/mind game with my opponent.
My solution would be:
1) Either keep the infinite chain intact, but let us feint an attack and continue the chain where it left off.
2) give us some kind of combo finisher unblockable (this is a zerker we're talking about, harassing in close distance with the mighty twin axes, gotta count for something). I believe orochi has one for upper attack on its 2nd hit.
3) Keep everything the same, but let us continue our chain attacks on multiple opponents at the same time (hitting one opponent then on its 3rd attack, chain to the second opponent and continue it) after it reaches its 4th attack which goes into infinite chain buff, give us a minor defense boost with its uninterruptible stance.
For me, I like the first one, I don't want a damage buff to zerker or something easy. I really wanna keep zerker on its "hard" difficulty of play, I love that.
PS: off-topic, I also really wanna try out a warden as i'm all about looks than gameplay ;p .. but after maining a zerker for a while, the warden (or any other hero) really felt so.. "simple" and kinda clunky.
EDIT: Only because I chose the first solution is due to zerker being the only hero who can cancel a light attack on a dodge (I honestly don't know any other hero who does that, if there are, then i take it back

)