MST
I've flow with Ryanair 5 times to/from Maastricht and it's a very long journey from Utrecht where I live. Even with free public transport to the airport for me as a student, I think twice before booking a ticket from Maastricht. Maastricht's market is more a combination of pax from Southern Netherlands, Belgians and lots of Germans. I think MST would do very well for W6, but would serve a different market then Eindhoven. MST is too far from the Randstad (Amsterdam especially). I think routes to Poland (GDN or WMI) and Hungary (BUD) could work for them.
MST doesn't bring in a lot of tourists for Maastricht itself. That's why the tourist board is promoting a visit to Maastricht or Valkenburg and the province of Limburg. They are well worth a visit, but very unknown.