I never thought of "Generations" as a sequel, I didn't even know for a long time they were related. As far as I can tell, the main relationship between the two games is that "Generations" uses the same engine and assets in space combat as "A Final Unity".

FWIW, AFU is next on my list, I just need to... dig up an old copy of that too.

Shame GoG never got around to remastering either of them, but thankfully Claude has no problems helping here.