No, no A/C. I never use A/C unless it's absolutely necessary. It costs 7-12MPG+ depending on conditions.
I use the OEM Bridgestone RE92's in the P165/65R14 flavor. That size was specifically made for this car and are much different than the larger RE92s. Using even the Michelin Energy Savers results in a 7-10% reduction in mileage, you can forget a regular tire. I'm not looking forward to the day that they stop making the RE92s. Need to stock up!
As far as taking the 444k mile car out on a road trip.. I wasn't nervous at all. As long as the hybrid system of the car is working properly, there isn't much to worry about. About the only thing that can leave you stranded is if the DC-DC converter stops charging your 12V battery - equivalent to having your alternator go out. They're very reliable cars overall, once you know a few things.
Actually, I did find out the hard way that the auxiliary 12v starter doesn't work on this car. We were out at her grandparents place, and I accidentally left the ignition on. When we came out, the hybrid battery had been drained, and I got nothing but a faint click from the 12V starter.
I just pulled the negative battery terminal to reset the computers, and it happily started with the IMA motor like normal. I could have also push started it.