I'd invest in New Center/ North End area- both upcoming areas, close to the city (8 mins) and a LOT of investment happening in the area. I would still take a look in person since Detroit is block by block. I live in the North End and I am very close to 3 major hospitals downtown, Wayne State university and CCS. There are so many students and traveling professionals. I rented a room in my home this past summer to great tenant who was doing an internship in Detroit $1100/ month! I would say these areas are also great for midterm, great for short, decent for long term- very close to all that downtown & midtown Detroit has to offer!
I hear many people speak of Detroit suburbs or the outskirts but not much about the inner city close to downtown. As someone who has lived here for the last 2 years, I have been in impressed by the amount of investment going in and around the downtown areas, much more opportunities to come in Detroit!