Has class balance improved since last year?
Engineers are currently top tier, so things have definitely changed. Rangers are also very popular in PvP right now.
I would say balance is better in the fact that every class has at least one competitive build in PvP, but still suffers from a few meta builds and not much build diversity.
Rangers got a lot of love recently. Especially their longbow.
Warriors actually got nerfed a few times too.
This thread belongs better into the profession balance section.
But short answer to your thread titles question: No, not really.
My opinion: Overall, since launch, the balance changes have actually felt like balance. Initially there will be boos, hisses and cheers, but over the longhaul they have panned out. The Warrior adrenaline change has, in my opinion, been the starkest and roughest.
That said the game is still the same game and if you stopped playing because the game itself became unappealing, that will likely not have changed. It may have a bit of newness initially upon returning, but that quickly fades.
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