Just downloaded all three XR's and WOW! Great job to all involved.

Can't wait for the XR-2 VC!:dance:
One small issue, I run in 1440 res so I use the 1600 panel and scale it down 10%. The problem is the characters on the displays (mini hud, timers, tank levels etc.) are all clipped; 8's and 9's look like 3's, 7's look like 1's etc. I'm not a programmer so I don't know if it's possible but it would be nice if there were a way to configure the font sizes to prevent this.
I have just done some extensive flight tests in the XR-1 and humbly offer some recommendations (I haven't flown the 2 or 5 yet but the systems look the same so should be applicable).
First; in the event of a system overheat there should be a backup airspeed and alt somewhere (pretty sure the FAA would have required this for certification). The DynP and StatP still function and that is all that you need to determine AS & ALT. However it's a little tricky doing the math in your head while attempting an emergency decent and in-flight radiator deployment. Could be displayed on one of the smaller now unused displays, like the MDA).
Second; the ability to reduce electrical load to slow the heat increase such as a non-essential avionics breaker. It could kill the HUD, mini HUD's, one main MFD, MDA, autopilot etc. Pull the breaker at 80deg and buy yourself 5 or 10 extra min until you hit 90degs. At present with everything you can shut down manually turned off you only get an extra 3min from startup to 90deg. (anyone else think emergency procedures are fun!?)
Third; a backup gear extension for when you run out of APU fuel (FAA would definitely require this one). Since most engines can run on fuel types other than those primarily used, maybe an RCS>APU Xfeed. The APU could burn itself out after a limited run time due to the higher fuel volatility but you would have enough run time to deploy the gear and radiator if necessary, like 80sec.
Lastly a few very minor, "would be nice" things:
-attitude hold autopilot bank increments 2.5deg instead of 5.
-a configuration option to remove the redundant alt & v/s readout on the HUD
-lockout the actuator switches if the hull temp is too high. (at present they all become, "push to die instantly" switches in the upper atmo.)
-currently things fail exactly at there listed max DynP, would be nice if they failed at some point slightly above (within 10%).
-a visible GPU plugged into the ship on the ground when ground cool is active
-ground cool could also be ground power so no APU fuel need be used
Thanks for considering these ideas. Once again truly great spacecraft!