I think you mean the sputtering thickness of the conductive gold on the diaphragms?? (I changed your title accordingly)
Two points on that:
1. Sputtering thickness does not seem to have a direct, audible effect on the quality of a Neumann capsule. Neumann used a low sputtering density on its capsules in the 1960s (f. ex. their brass K47/49/67), yet, these were just as good in terms of measurable and audible quality as those, later on, where you could no longer see the outline of the backplate holes through the sputtering (the feature your were referring to).
2. The red flag and alarm siren went off when I read "re-diaphragmed vintage capsules". I hope you realize that all of them are junk, compared to the exquisite quality of Neumann's products. In that light, the sputtering density seems to be almost an afterthought in light of the enormous quality drop that third-party re-diaphragmings present.