Hi Jawine!
It is possible to coat cotton tape with shellac, but extended exposure to water can be a problem (causes clouding of the finish and some stickiness). Urethane finishes can make cotton tape many times more durable and doesn't have the same problem.
It sure makes for a challenge removing the old tape, however!
Have you considered yellow vinyl tape or some of the old Benotto cellotape that sometimes shows up on eBay? That gives the color and durability, resists stains, and isn't too slippery when wet (there's some surface texturing, like a fine cross-hatching or a file tread on a sew-up tire).
I like the idea of some yellow in there! Housings aren't a bad idea....
I did the harlequin thing once. I saw argyle patterns for a week afterward. That's a fine example in your photo, Pete, made moreso by fine symmetry and the pattern reversal at the brakes.
Best,
Dan.