Using UV spacing is not that accurate in 3d space. For accurate grids on surfaces, something like panelingtools needs to be used: Equal Grid Across Surfaces - #10 by scottd
And also, not all shapes (in fact very few) can be covered by planar, square panels that can be unrolled to flat without stretching. To handle doubly curves surfaces some stretch or play needs to be introduced at the joints or in the panel itself. Reduce number of panel units for mapping double-curved surface - #16 by scottd
That post was quite old. In Rhino 8 there is a replacement for Shrink Trimmed surface that needs to be replaced with a newer one.
This is the updated definition for 8. It requires that PanelingTools is installed. Grasshopper should prompt for that when the definition is opened.
Equal Grid Across Surfaces Panelingtools V8.gh (48.5 KB)