The climb south from the Englewood trailhead is tough for a rail trail.
Mickelson was also a fun ride, although not as "warm and fuzzy" in the sense of cute little towns conveniently spaced. Fortunately, there are nice trail rest areas, including some with water cisterns and shelters from both sun and things like hail. Not much in the way of authorized/legal camping outside of Hill City, Custer and at the southern terminus in Edgemont. And be prepared for noticeable grades. The climb south from the Englewood trailhead is tough for a rail trail. It's worse if you start from Deadwood. And it takes you to over 6,200'.