Ya, certain skills should use up bits of your chain. And the pulsing red could be done by looping an animation (or just changing the character's graphic with a script call), but that's just a visual nicety and doesn't really matter. The added strength makes sense, in terms of magic. Your body is enhanced by the magic you're building up, then it goes back to normal once you release it all.
One skill that would also be cool is a power that unleashes your entire heat chain, regardless of the amount. The damage it does would be proportionate to the amount of heat in your heat chain.
And that's all my ideas on the subject :p