did some quick reading on uni's the other day when i first read this....

angle doesn't matter regarding keeping a constant output velocity, a single uni produces a sinusoidal velocity (varies up and down like a wave pattern) but the fact there is two uni's... one at each end of the shaft... means that this effect is cancelled out by the second uni... and therefore you already have a constant velocity

i assume that by reducing the angles you reduce the energy lost in translating the torque through the uni... therefore you are just trying to minimise drivetrain energy loss? is that the aim? or are we trying to achieve a constant velocity?