Nothing much really tbh. You still use your 1-2-3 combo for building up hate, but there's now a dot combo you can use and a huge damage combo-ender instead of Rage of Halone. There's also some others added as 5 new abilities were given to each class from L50-60.

Controller is completely doable in any class. I played with White Mage (healer), Monk (DPS), and other tank classes like Warrior & Dark Knight. Haven't encountered any problems yet. If anything, healing can be an issue on controllers with the toggling you'll have to do by pressing R1 & L1 for all their party targeting commands.

I haven't played on PC so can't use anything as reference but moving around has to be a pro on pad as it is effortless.