Your eyedoctor can show you the capillaries in question next time you get your script renewed.

No, the capillaries on your eyelids supply o2.

If you fall asleep with contacts on or wear them too long, blocking the supply of O2, you will grow capillaries infront of your cornea. This is bad for vision.

Have you seen how big a hang glider is? That’s roughly what a human-mass creature needs to fly.

Theres a few companies that make moving tails (and wings) for a few hundred USD, but they tend to be waitless rather than designed for balancing