"Geometric Grid" Boy's Indigo Underkimono

This listing is for a vintage Japanese child's underkimono, meant for a little boy, that we overdyed in indigo.  Originally it would be layered underneath a miyamairi kimono, which is a ceremonial kimono worn for festivals and very special occasions. The light blue color confirmed that the fiber is synthetic, which normally does not take a dye very well.  It has a silky feel and sheen, but alas it is polyester. The underlying pattern is a woven grid, and the kimono still has the long ties at the front collar that would have been used to close it.   We hope some creative artisan will claim this little gem as a base for an embellishment project - embroidery?  applique? painting?