I think that #Brussels should add a 4th kind of rail offer to its public transport mix:

A #lightrail system akin to Germany‘s #Stadtbahn systems, situated between the #Tram and the #Metro. #citytrain

You start that by buying #TW6000s from Budapest and Hanover (or similar vehicles from the Ruhr and Tunis).

https://en.wikipedia.org/wiki/TW_6000?wprov=sfti1#

TW 6000 - Wikipedia