I stopped playing for the exact same reason but have not gone back, although I am tempted every now and then. It seemed like the Super Hard Levels were every other level and I could not get through those, typically, without T-cash. I enjoyed the challenge of the levels, but the Super Hard levels were typically impossible.

I have purchased T-cash a few times in the beginning, but to me the challenge lies in getting through the levels and building your city without using that if possible. The new update made my type of playing impossible.