>>41788520Que me thinking USUM actually made some improvements. (Lusamine's changes made sense to me and how it blended with her kids drama still made sense. The family got a more satisfying ending with god damn closure, we got a better climax and so for.)
Biggest problem with Ultras story is that most of the tender moments revolving around Lillie and her family issues from SM are NOT the big focus of Ultra.
They are still a major part of the story, but the focus is more on you, Necrozma, Ultra Space and the whole of Alola.
What is more, certain things from SM are either taken out, happen at difference places in different times... or completely happens off screen. Some of these made Lillie's arc in particular... weaker. (Despite most of the beats still being there and her actually being in the post game to show her growth.)
Building up to the whole Necrozma thing is the Ultra Recon Squad who were not implemented in the story that well... in fact some moments are kind of forced.
Those could be justifiable reasons for preferring SM over Ultra, that is up to preference... but know that Ultra has wrapped things up much better in comparison.