Well… what a great thread. We’ve been toying with things also in the GOAT community (@sudokita and @dornawcox ), workadventure seems great but yes the licensing issues not great.
That said - most of the effort is actually in creating the tilekit and stuff, which Greg Gage (or someone at BB) has done so nicely - so honestly if and when a more completely open source version appears it won’t be hard to switch.
Anyone care to share great places for tile sets that you’ve found. Searching produces many, but would love opinions about the coolest / best tile sets to build out your world!