Becoming a permanent quasi-vassal isn't that bad. From experience, 3 months down the road the vassal status will be as good as forgotten (see: Morek/Aquilegia). It should be somewhat acceptable when faced with the alternative of total destruction.
In the case of Summerdale, they decided they would rather be full vassals to Astrum than quasi-vassals to Morek. Is this better? Maybe - it was their decision.
Some of them decided they would be
part of Astrum, and the rest that they would simply emigrate.
Pre-war Summerdale was boring as hell, the same as Libero Empire before and after the war, I suspect. No matter if the vassal status exists or not in theory.
