Every car and every owner is different. Just one question and one comment:

1) How much money and trouble have you put into items that aren't normal wear and tear? Every car made will need brakes, timing belts if equipped, coolant replacement, etc. in due time.

2) I keep quite detailed records on what my cars cost in total to run per year or per mile. My 95 850 is so far the least expensive car to own of any I've had, including in increasing order of cost Volvo 240 & 164, Saab 900, Acura Integra (a distant last place). On all of these I've done most of the maintenance and repair work. What work you do vs have done and when might make a big difference. Volvo dealers for instance, can be very unreasonable, as you well know.

It might be worth breaking your expenses and time/effort down into unavoidable wear and tear vs nuisances and serious problems. Then you can decide if you could likely do better in a different car.