I agree; while having mods that resolve major issues is certainly better than nothing, their very existence reflects poorly on the developer.
That said, the value that a robust modification ecosystem can add to a game cannot be understated. Skyrim is a fantastic example of this.
In addition, mods aren't a great option since doing so marks you as a "cheater" or disables achievements, etc.
I generally agree with your conclusions about SimCity (2013) though; generally great UI, but tiny city sizes, online services dependency (which is greatly mitigated now as of the "final" patch), and some of the "streamlining" done to the game.