It would be nice to have a curve that starts going up fast, then flattens out, is flat at 0.5 for most of the interval, then speeds up and goes to 1.0 near the end in a mirror of what it does at the start. Sort of the same as inOut curves, but with the gradient starting at >1 instead of <1. An inverse S shape on its side.

cc @marcoms in case you're interested in doing that. :-)