What spec are you? Because honestly the berserker spec seems rather underpowered to me. The Guardian spec has a block, even when using a 2-hand weapon, that you can use to 'parry' which stuns things and has a very very tiny cooldown. Makes it slightly easier, but it does take a lot of practice and paying attention to what's going on. Also, I've noticed, if an enemy has stars around their head, they seem to be un-stunnable, even if they've gotten back up. So make sure to hold your cooldowns and stuns for that.
Ranger on the other hand is positioning and then spamming M2 with a crossbow. Got my ranger to 45 from 17 last night by just farming bosses solo. It's so ridiculously easy that it almost makes me feel bad. That said, I plan to start trying out more difficult content and starting to farm for Yellows(still haven't gotten any yellows except my lamp) when I play tonight.