Here's another thing that you should be able to do but can't…
The Warp Function at the moment is not repeatable, Transform Again does not allow you to repeat Warp transformations. There is only one way to 're-warp', and thats to record an Action step which will perform the same transform. Analyzing this Action step, its possible to see that the co-ordinates "rational points" and displacements from these, seem to still require a relatively small amount of data. So being able to repeat them in Transform again (Command Sift T) should be within the bounds of possibility. As far as I can see. Within my limited knowledge.
Also in the Options bar, while using Warp, or for that matter any Transform, the possibility to save out loadable grids and co-ordinates would be useful.
While we are on a similar subject - it should surely be possible to load in saved Liquify Grids as part of Actions also.
The thing I miss about Liquify is useful applicability as a Smart Filter.