Side note - recommend something like this (Over The Door Stroller Storage Hanger) for storing stroller out of the way on the back of the door if you are limited in storage space. This was a life saver for us when we were in a small apartment.
https://www.amazon.com/gp/product/B001GPBJP8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
And +1000 for using the structured carrier as much as possible for city bus/metro travel. Elevators are always out on the metro, and even when they are not many are inconveniently located/difficult to find. The only bus I found that it wasn't too bad to use a stroller was the Circulator during a non-busy time. The Circulator (when it wasn't packed) would allow you to keep the stroller unfolded with baby in it and had an area where bus seats flip up where it can go, but it still was challenging getting the stroller up to bus level to enter the bus (even when the bus is kneeling) and navigating the narrow entry area. Not sure if they have changed the rules on the Circulator or not.