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Test R2 with a test plate, then flash polish R1 and make sure your lens focuses starlight (*) where expected (can't remember what glass you used, let's assume BK7, so for given prescription it should focus at 1414.5mm). Make sure you test it reversed (with R2 facing the sky) as this way residual spherical is much lower.
If it focuses as calculated, polish the R1 fully and re-check. If it is still at 1414.5mm or thereabouts, check if wavefront seems smooth (as per Zemax simulation attached). No need to test the lens any further.
It takes more than 20 waves of asphericity to change focus and shape of the Ronchi bands significantly. If surface was this bumpy your full size lap would be dragging and skipping and jumping all over the place.
(of course you don't need to use real starlight, any decent scope will provide good collimated beam)
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