Jeff,
Did your .023 birch veneer have a paper backing? I see lots of sources for veneer with paper 10mil backing. Did you glue it on with the backing?
I did some calculations and it seems that using 1/64 ply skins is only slightly heavier than using 1/16" balsa but is more expensive depending on price of balsa sheets. However it is easier because it is in larger sheets. The birch veneer is really heavier than both ply and balsa plus the weight of the paper if it is used.
I really would like to avoid edge gluing balsa sheets. However the largest 1/64" sheet I can find is only 4' x 4' and would have to be edge joined also.
The price of the birch veneer is really good but I'm concerned about the overall weight.
Gary