Another Minnesotan here, though central MN and not Minneapolis, my husband and I usually travel to the cities for pleasure at least once per month. It's a very thriving area. Politics are progressive and lean very left. Schools in Minnesota are generally good, though you'll want to look around at places to live that let you into a school you'd like for your child (things like language immersion programs, charter schools, etc.). Minnesota is a great place for kids based on the Annie E. Casey Kids Count data:
http://www.aecf.org/resources/the-2016-kids-count-data-book/ (Surprise: MN is ranked #1 for kids).
I will also add that the metro area has an abundance of arts/culture (theatre, music, museums), and there are many opportunities to be active, including outdoor activities all year (swimming, cross-country skiing, hiking in the many state parks, etc.) and people really celebrate winter--for example, the various winter events like Crashed Ice, St. Paul Winter Carnival, etc. For older adults/seniors, we have excellent health care facilities, lots of support for aging in place, and ways to stay active/busy. And, major sports teams and venues for big shows, if you're into those things. Also, the number of libraries and book stores is huge (I'm a librarian).
My sister went to graduate school at Pitt so I've been there a few times. I will say that my impression of Pittsburgh is that houses are generally older and you have less yard/personal space. Traffic also seemed kind of crazy. Minnesota spends a decent amount on infrastructure so road work is a hassle during summer months, but it's well worth it.
I have heard it can be hard to make real connections with people here (a lot of people who live here are "born and raised" types so they have friends from childhood they still hang out with), so if you do decide to make the move, getting connected with a group of some sort (church, club, activity of some kind) could help ease the transition to making new friends outside of work.