1) Real watts or bullsheet LED equivalent watts?
2) Are you math challenged? Yes, double the wattage will always be about (if not exactly) twice the heat than what your headlight enclosure was designed to endure.
3) This is illegal for use on public roads. Unless you live in some 3rd world country where it's all about screw-you.
4) Yes an excessive amount of heat will eventually make the wiring insulation and/or connectors foul or at least get brittle. This is a modest increase in wattage so it is unlikely to melt the wiring, but depending on what else is on the circuit you may end up with a blown fuse if you have the circuit overloaded.
5) Why? If you can't see at night you should not drive at night. Blinding other people is bad form and creates additional danger and meh, just get the fsck off the road if you can't see using stock wattage bulbs or properly engineering aftermarket housings if you want to switch to LED or HID bulbs.
Stepping back a moment, if your only problem is you have polycarb lenses that are UV hazed, either get a refinishing kit for them, or the DIY options to refinish are out there, or buy new headlight enclosures.
Stuffing a double wattage bulb in is a bad idea and wherever you got that idea, should be abandoned as a sane approach to vehicle lighting.