The problem with that idea is that unless it's your land and your money you can't dictate what others do with their assets. Well, you CAN dictate some, but developers don't love that and may decide not to develop at all. If Opus, for example, purchases an entire city block and wants to develop a stout, 10 story building in lieu of a massive 40 story slim tower, that's their business UNLESS there are some city codes and zoning laws that prohibit those types of developments (like you elude to). However, if that makes the development more expensive with less overall profit for the developer, the project may be a no-go.As much as I'm exited to see these blocks get developed I'm apprehensive as to the reason they're being developed the way that they are. Full block developments in short stature are terrible for future development, regardless of being new development or not. Look at the core of downtown. The only way to build there now, is to tear down a building that already exists, for the most part. DTE is getting a boost from the stadium no doubt, but downtown as a whole has limited space. Build higher on a smaller footprint, and you gain availability for future investment if not speculation. Build a 9 story block and its locked down for a generation. In the mean time, green space could be added that would attract said speculation and lead to further development. Besides, you must build higher on the periferi if you want to maintain the hat like structure of the skyline, because it drives taller development to the center. There is a reason why one third of downtown Minni was razed in the late 50s and early 60s. This is it.
So even though I agree with you 100% that development should never utilize more than half a city block at most, it's not wise for the city to enforce such a rule in a market that frankly is never so "white hot" that it can do whatever it wants and developers will still be happy to build there (like Manhattan, it seems).