Just to get it out of the way, not a fan of the time skip in almost any media. It creates a disconnect and by the time I'm done reorienting I've missed at least entire scene.
...but I love this couple so much (and gremlin-Kasane at her best) that I can't knock it too much. The ending vibe is exactly what the author has been aiming for the entire series and really gives it that bonafide slice-o-life feel. It's interesting that Subaru refers to her as his "partner", is that a stylistic choice on the part of the TL or an actual Japanese term?
Either way, couple goals

Speaking of gremlins...just wanna highlight the
dangers of glitter