I've tried for a character with high evasion and dodge and what I found out it's that it's not reliable at all. I got at best one out of 3 dodges. Dodge and evasion is not supposed to make you untouchable, they are damage mitigation much like like any armor, thing is, armor reduces damage per attack and dodge/evasion will every now and then make you completly avoid an attack so it kinda balances out how much damage both mitigate.
Here's the thing though (and note this is my personal opinion, not everyone has to see it that way). With an armor, you just put it on and the damage mitigation is there. With dodge and evasion you are effectively wasting skills points.
So is it viable? I suppose it is, but it certainly is a lot worse than just wearing armor... As for mellee as a main focus, I'd say it's not impossible by any streach of the imagination, but it's probably the hardest build. I see mellee working better as an alternative, as your secondary attack type rather than primary.
So if you're idea is making a martial artist... Well it's possible, but you're in for a world of pain.