I used LED's and have never used EL tape before but I like your design.
Transparent filament swapped out at 1-2mm with a dark metallic filament might look cool.
Could perhaps cnc strips of transparent acrylic and paint them instead of printing them. Could even invert the design use the smooth transparent surface as exterior and paint/fill those engraved interior features.
Could maybe use LED strips and run them down channels engraved into acrylic.
Could just power them with a half dozen cr2032's. Just slap on some decent vhb and presto!
As someone who has experimented with ground effect lighting on their board for the sole purpose of ez night riding on dark, mostly unlit streets without a flashlight: illuminating the ground is more visually impactful as well as useful for general area illumination without disturbing one's night-adapted vision.