DH and barb are pushing further than any other class. They also have the most variety in their builds. If you play crusader, you're stuck to condemn or pony build, condemn being stronger, if you play WD, pet can take you kinda far, but Jade is really what is used. If you play Wiz, Things will change in 2.2, for now firebirds is the only viable, but it's still weak as balls, 2.2 will make Tals the strongest, so a standard tals build will be good. The new Slowtime set will be pretty strong too. If you play Monk, exploding palm and wave of light with sunwuko's seems to be the only way to play, but at least its fun. DH has Marauders, which is good, and has 3 or 4 build variations alone, Nats is getting buffed, which will be super strong with at least 2 build variations, and they are getting a new multishot set which looks quite promising, should have 2 variations as well. Barb, well... they'll have upwards of 12 INSANELY strong build variations, and may be the most versatile class in the game at the moment. Play for Crusader and WD won't change much in 2.2, crusader will still be running around in S patterns with condemn providing support by grouping monsters, and WD will still be the horrify party boss, neither can push too high in solo play, and to push anything substantial takes some insane gear, DH and Barb can do those grifts with significantly less gear.
All classes, given the best gear, and best players, can make it within ~4 grift levels of each other. DH and Barb take less skill, and less gear, to push to decent (~40) grift levels. Monk is right behind them in power, still pretty easy to play, crusader follows, then WD and Wiz, Wiz being the least useful in group play (at the moment, slowtime set will change that), and very hard to solo those grifts with.
Either way, you can't "play your style" if you want to push ~40+ grifts. You need to play the set builds, no matter what. They out class legendaries up and down, and most sets aren't free forming allowing you to build new, interesting combos, they really push you into a specific play pattern.
If you don't care about getting crazy high, and just want to play your way, then any class is about equal, and with solid legendaries, you can push grift 30ish, but people here are reddit will rip that apart saying its basically useless to play a build that can't go higher than 30, even if its what you enjoy playing.