RE: waterproofing esc and rx
Hi
No it will NOT compromise the cooling at all, just leave the ends of the heat shrink open as it comes out of the box, if you are worried about splashing into and onto the ESC just make up a guard of some type, I honestly have an exposed ESC and it gets splashed all the time and keeps on working without fail,,,, Spray the Receiver too it will keep on working no problem.
Dan