Ideal ripple current on a DC to DC step down switching regulator
The term "ideal ripple current" is valid. I have used the term "porching factor" to define this. Marty Brown defines a ripple factor in his book which is correct.

The ripple factor is important because if it's too small the orthodox current mode chip won't have a proper ramp to sense and you will get instability and/or subharmonics, and you may have to fight with slope compensation to get the thing to behave.

There is good credence to the fact that if the slope compensation was large and ripple factor or porching factor was very small then you are almost back to voltage mode anyway. So, too little ripple is BAD in current mode.

Now, if ripple is big then it is true that peak currents are higher than "necessary" for a given output current.