Add more evenly distributed vertices to your deformation spline, makes it more painful to work with but it should fix the uneven length of the ridges somewhat.
I'm trying to do the same, I can retopo it, but merging all the vertices is a pain, the tool linked can save you to do that, but still nothing that works with an animated sim :(
Your model lacks optimization, you have a lot of edgeloops/vertices that don't do anything. I would recommend looking into highpoly modeling, sub-divisional modeling etc.