Seattle has zoning out the ying-yang, and the streets specifically need to be zoned to townhouse height to build the townhouses. That designation has been spreading over the last decade+.
As far as aesthetics, just go to a neighborhood Design Review Board meeting, where the dozen or so busybodies in each neighborhood go and throw rotten vegetables at developers for hours, ruthlessly hounding them to get their designs more in line with the aesthetics of the busybody junta.
(A sufficiently small townhouse project can evade the board, much to the chagrin of the busybodies).
The problem with the townhouses is not that they're ugly or don't "fit in" but that too many of them get build without parking, as the anti-car elements on design boards and in the gummint browbeat developers into not offering parking.
I looked at a lot of the new Ballard construction when house shopping in 2013, before buying a condo in another 'hood, they're not bad, the kitchens especially are generally being done very nicely, but you can't please everyone with how they look from the outside, I guess.