The average owner changes the oil every other year (when the oil pressure idiot light comes on), the coolant on the seventh anniversary, the brakes after they run into a car in front of them, and the half flat tires when the steel belts are rubbing on the road.
Average is irrelevant, given your stated approach to maintenance.
Keep up that regular maintenance and you'll be enjoying your Camry for a long time. Our '98 Sienna (same 1MZ-FE engine as the V6 Camry) has 277,700 miles on it. We drove it from Kentucky to Canada in April, and to Florida in June. 24 mpg and comfortable cruising all the way, and I'd hit the road for a long trip first thing tomorrow morning without a worry (because the maintenance is current).
I agree with TedL -- Because you're not racking up the miles, age is going to become a factor for you the same as mileage in your situation. In addition to rust, things like vacuum leaks may start appearing due to hoses and connectors starting to age. It's nothing to lose any sleep over, though.
With regular proper & preventative maint. Stuff like fixing cracked hoses is routine after a certain amount of time anyhow. but take care of them before they become an issue and your Toyota will last you a long long time
Maintenance is key! But I've set the mine at transmission failure or headgasket failure that will take it out. Since my compression numbers are solid, I'm just looking at the trans. If the trans fails, my car is out. Everything else for me is just minor repairs and upkeep cost...