First things first, if u mood Roshi 65% +life and you still die in round 1, then that just means you were outpowered by the opponent.

If you mood roshi to deal damage, then he can't really be counted as a tank.

Most teams utilize Roshi for dmg thinking his passive of stacking def and ninjutsu makes him a real tank. It doesn't.

Han on the other hand is a real tank, and you can see that his dps lacks when compare to roshi, which is why he is always paired mostly with water main for poison tai to make up for it.