Guild Wars 2

Honestly, it's pretty stupid to run more than 1 kit since you would not be able to buff 2 kits with elixirs and you would end up with more skills than you could use.

This is the flamethrower build I use
http://www.guildhead.com/skill-calc#MzMz...0x0VokqMka

a couple things about it
-Since the 1 key is what you use more than anything else, I feel like increasing burn duration by 20% is better than reducing flamethrower CDs by 20%
-Using the rocket boots gives you another burn source
-Going into incendiary powder gives you a 3rd burn source
-Stack precision, to increase incendiary powder effectiveness, and condition damage obviously.

The grenade kit is still superior to the flamethrower in single target and AoE damage, as well as survivability. Even if the flamethrower talent gives 200 toughness, the fact that it's still in melee range makes you take much more damage than the HUGE range of the traited grenade kit. The biggest benefit to using flamethrower is that you're not completely screwed by moving targets. The grenades take a long ass time to throw and are all ground targetted.

It is very fun though =P