Hey @PHL City Planner! Your profile is similar to mine, though I'll be applying at least one year behind you. I have a graduate degree in an urban planning/architecture-related discipline and currently work at the city level, so I'll be following your 2019 application journey!
I'm also interested in domestic/urban policy, so HKS and WWS are my tops, too. Harris is also on my list because of their Place Lab and the fact that they seem to funnel a lot of their students into internships/jobs with the City of Chicago. (I am also from the Midwest and love Chicago.) However, the lack of certificate or true focus in urban policy is a bit of a deterrent. It may be worth adding to your list, though!