Flights between FWA-ROA via DTW are operated by Pinnacle or Mesaba. The CRJs are operated by Pinnacle and the Saab 340 turbo props are operated by Mesaba. Both are separate airlines from NWA and both operate their own maintenance department as well as employee groups. Big daddy NWA oversees to a limited extent the daily operations of both airlines, but in your case the shots were called from MEM or MSP.
The mechanical delays are inevitable... every airline has them and will continue to have them as long as they operate airplanes.
The crew delays can happen at any airline as well, but some are more prone to them. Pinnacle is chronically short staffed and Mesaba is experiencing a few growing pains at the moment. I know that Pinnacle has a lot of aircraft swaps built into their schedules which will exacerbate a delay. At Mesaba we usually keep an airplane all day unless we have long breaks or we happen to be flying an airplane that needs routing to a maintenance facility and we are going elsewhere.
Sorry to hear about your experiences, but unfortunately these are the realities of the business. I hope the next time you fly it goes a little less painfully.
AZJ