So, basically, what you don't like about the A is the costs of repairs, access to repair shops, and limits on where you can park. What you don't like about the TC is the small space.
Costs of repairs - a TC, B, C, 5er and TT will all be less expensive (all things considered) than the A in terms of repair costs. All will have similar costs relating to windshields, engine work, etc.
Access to repair shops - again all the others will have basically better access to repair shops. The C (and possibly the B) could be slightly more limited due to a shop's lift (my mechanic has only one lift that can handle my 21ft C, whereas there are 4 or 5 that can handle pickups and vans).
Parking - this comes down to what parking you are talking about. If being able to park and camp anywhere, the TC and B are your most versatile. If being able to stop and pick up groceries, visit a museum, etc., then the TC, B and small C can all work fairly well. If being able to set up camp and then drive into town and park anywhere, then the TT and 5er are most convenient with the TC following.
When I first started looking at RVs, I originally wanted a TC. I had grown up camping in a SixPac TC and really loved it. When I started looking around, I realized how much bigger the TC felt to a 10 year old kid... For me, I realized that a TC or a B were just that much too small for how I wanted to camp. An A and 5er were way more than I needed or wanted.
That left the TT and the C. I picked up a cheap TT to try it out, it was 18.5ft and the size worked well. But, I didn't enjoy the extra length on the road. So, I got my clipper. At 21ft, it is very close to the same interior space as the TT - gained the overcab bed, lost a touch of floor space - but I am about 13ft less in overall length while driving.
Now, I don't live in it full-time and I don't spend a month straight in it. But, I think for me, the placement and size of windows has more affect on claustrophobia/cabin fever than the actual space in the RV. My clipper is older and has big windows on all three sides, plus the windshield, and the overcab bed has windows on the 3 walls. I only pull the shades when sleeping and don't have a curtain between the cabover and main area. That keeps the RV feeling much brighter and open (fellow clipper owners always mention how much bigger mine feels even though we have the same floorplan and length).
A TT or 5er would allow you to easily drive the truck into town for a movie, etc., if you get real stir crazy. Unless you routinely dropped the TC from the truck, you'd have to break camp to go to town. And a B or small C would always require breaking camp. Bigger C and you could add a toad, but most likely not your truck, so is that something you'd want to do - trade the truck for a car?
The above isn't to say any one thing is better than another, but just to throw some thoughts out that might help you decide what will work best for yourself.
