You can use your reticle for hold corrections on any power. A hashmark is a hashmark is a hashmark. It just doesn't translate to an easily determined number of mils/moa so you are right in that you can't dial a correction based on reticle impact.
I actually prefer an SFP scope in many situations. Most FFP scopes split the difference on reticle usefulness at min and max, and for me that usually makes the features at max res too thick and chunky.