I've got and idea for a new mech.

Skyfall.

Role: attacker

HP: 250 000k (max rank)

Speed: 20kmh

Ability: kamikaze

Energy capacity: 32

Rarity: epic

Ability cooldown: 15s

Ability duration: 15s

Ability damage (dealt to opponents): 50k

Ability damage (dealt to self) : 7k

Ability details: Skyfall launches himself into the air and flies above the arena for 15 seconds. When he is flying he gains a speed boost. Weapons can face up or down. If Skyfall crashes into the ground or enemies, he deals damage to himself and his enemies in a radius of 5m. 

I fell that this mech is quite balanced and deserves to be in the epic rarity. He does a ton of damage to himself and his opponents. Plus there are no mechs to rule the sky yet.