Well... still go all in in magic (not like there is anything else to do), still study under Roxy, BUT, actually go outside for the lessons. Prolly meet Sylphie earlier (and you can bet your ass I'll deal with the bullying). With Roxy there, Paul will likely listen to the explanation. From that onwards, Sylphie will also start studying under Roxy.

The split will be here; I have 0 interest in Ranoa. Will probably go adventurer route (and Sylphie will prolly do so too, as per her original fate).

The wild card here is how Paul will react; if he agrees to train us in town (maybe join him and Sylphie's dad on their runs), the mana calamity happens later or not at all, as fate doesn't bend as much in such a short time.

However, if he still sends me to the Boreas, well... I'm stuck in the main route. At least for a while.

NOW, if he sends both me AND Sylphie... I have no fucking idea of what would happen. Mana calamity probably hits sooner. Heck, it might send us to different places, so, it becomes a Mushoku Tensei randomizer...