I used to think heat would be a problem, too, but I've come around. It's a consideration, but it's doable. Remember we already have some pretty high power sats up there, so it's not something we haven't already been working around.

IMO the big cash drain will end up being maintenance, as in, you can't do it. If you have a box or a power supply fail on the ground you can swap it out. Anything in orbit would have to be replaced.