Power Meters / Powermeters (SRM, Powertap, Quarq, Ergomo, Vector, Stages, power2max, P2M, 4iii, InPower, Cinch)

Apparently R/L balance is completely unimportant and of no bother thinking about.
Given it's an aerobic sport, not strength, I'd tend to agree.
Oxygen is the limiter.

You could use Vector pedals to work out if the Stages meter would be any use to you.