I'm not dead set against going back to Maryland, it is a valid option. I see no desire for it from either DC residents or Maryland residents though and I do see demands for DC statehood from DC residents.

There has already been a referendum on joining as a state - 86% of voters voted Yes: https://en.wikipedia.org/wiki/2016_W...ood_referendum

PS the proposal seems to be valid with the US Constitution as the Federal Government would keep a (much smaller) District.

As for it being a City State I have no qualms with that. There are many City States around the globe.