To be honest, most of the time your mitigation as a DPS class is irrelevant anyways because you are not supposed to tank bosses. Sure, for some fights you need some roughly 1000 HP or 10% protection more than usual to survive a nuke from certain bosses (archer mini boss in T4 for example) but other than that you should only go for DPS anyways.
No one needs a barb that got HP like a tank but the DPS of a guard. Your best way of surviving is hate decrease and the tools to fend off aggro if you got it.
For solo play it makes almost no difference if you got 20% mitigation or 25% mitigation, I rather kill the enemy faster than tanking it for too long.
Barbarians and Rangers got their own ways of suriviability, rangers got the range advantage of a bow and their traps to keep enemies at distance and barbs got many stuns and kicks, also some of them are AoE as well as the Blood Rage stance that makes you tankier by buffing your health (and regeneration) for each stack.
Aside from the survival aspect, I personally would go for a Barbarian. I got both classes on level 80 and the barb is just so much more fun, especially because you are not limited to one spec all the time like rangers are. Rangers got “revamped” and dumbed down so much that all specs look almost the same since all end feats besides the Linebreaker are a waste of points to get there and really underwhelming. Melee ranger (with Sword + Shield or Dagger) is probably the most boring way to play any class, as Evito already said, you got one combo attack from level 60 that is the only useful combo unless you buy / get the combo book from khitai on level 80.
As a Barb you can go for dual wielding or two handed and both in a DPS or more survival way, there are far more options to play this class than a ranger has.