I have no idea (other than cost) why this sticker idea has never been implemented. Nothing worst than the same boat stopping you 2 or 3 times in the same day. :wallbash:
I've got a couple of flash lights, a floating one and replaced the crappy one that came with the kit with a waterproof one. Another idea that was shared with me a while back was to have some glow sticks on board. No batteries required and last for hours as an auxiliary light source. If you're floating in the water at night, it would certainly provide some light for signaling. The other thing I have on my life jackets, are automatic strobe lights. Water hits them and they start to flash. Also have flares, have more stuff than you need to have and that can't be a bad thing.