Most people report that melee is brutal overall, the hit windows are punishing compared to ranged and kiting builds. I think Warrior will shine later on, but it's tough going. Act I boss took me 7-8 tries, after 5 or so, I went on a grind and gained two levels, I also changed my gear. I'm only level 23 so far, so I haven't even ascended, I'm excited to go for the Titan though! Regardless of difficulty, I'm having a ton of fun, I just wish I had more time to play this week (it's one of those 80 hour work-weeks that comes along every now and then).