Quote by Zel
I did that tree too. They are all really fun, just depends on how you want to play. I usually go Mania cause its massive risk mass reward style and my team can rez me if things go south.
I actually planned my Krieg as a Hellborn/Mania hybrid, I simply preferred to focus on my fire abilities first. I really think that the Mania tree is the core of that character, since that's the skill-tree that boosts his main ability the most (ie. Buzz Axe Rampage). I assume that most people will either go for a Bloodlust/Mania or Hellborn/Mania hybrid; otherwise they'd end up with a fairly weak Buzz Axe Rampage, which would defeat the whole purpose of that character.
And yeah, Krieg definitely is a high-risk/high-reward character, he's actually at his utmost strongest in near-death situations. That's why I called him a 'counterintuitive' character in one of my previous posts: you actually want to be taking damage with him, so many of his abilities truly shine that way. For example when I light myself on fire, although I steadily lose health, I gain +75% fire damage, +50% damage reduction, bonuses to accuracy and reload speed, and my Buzz Axe Rampage regenerates sooo much faster. Krieg isn't called a 'psycho' for nothing, he's genuinely stimulated by pain, haha.