To me, the always-on DRM was the deal-breaker, the small city sizes just make it easier for me not to buy it.
I can understand the decision to enforce small cities because it would be too intensive on the CPU to run the glassbox simulation on a larger scale, but what in god's name possessed them to spread out all the cities in a region the way they have? Once you've built up your city to a high density what you see is rectangular clusters of high-rise buildings surrounded by hectares of wilderness, which looks ridiculous. The cities in Sim City 4 butted up next to each other, so when you ran out of room to expand (which took a long time) you could move on to the neighbouring city and at least continue the illusion of them being one big city. The way they've done it in this new Sim City just looks asinine.