This is for a low magic campaign (No full casters. Partial casters are fine. Ex. Rangers/Paladins and similar). This means sources of magical healing will be pretty lacking and I'm looking for a way to heal easily before encounters. I really like the idea of the Warshaper for 2 reasons. I really want a good excuse to play a Warshaper and the fast healing from Warshaper 4 will be extremely useful between encounters. For fast healing to be useful I need to get there ASAP though. This means I need to have Full BAB so I can take Warshaper by level 5 and have fast healing by 8 (the campaign will likely end around level 9 since my DM doesn't like high level games). With this fast healing I was looking more to become our teams primary tank so I can soak up damage each encounter without issue.
I was looking at an unarmed form of fighter to get this done since I can equip heavy armor and it can use the natural weapon size increase from Warshaper that I found here: http://community.wizards.com/forum/previous-editions-general/threads/1961271
Is the unarmed version of fighter better for damage/tankiness, is there another build stronger that does something similar to another class, or would simply a fighter build using a weapon increase my damage (I prefer not this route if possible but I'm not shutting the door)?
What would be an optimal build for tankiness + damage with Warshaper by 5? (I'm open to other races or classes.)