I mean, we've got everything for a great Ralsei Weird Route AU. Now that it's confirmed he can perform powerful fire magic that he deliberately keeps hiding form us, what if in chapter 1 he just... didn't do it and Fireshock (or whatever name is good for it) was available from the very start? You could perform actions similar to the actual weird route which would end up with him Firegraving (again, needs a better name) for example Susie in her forest bossfight. Or you could go another way and make the route centered around you somehow trying to mentally break Ralral into allowing you to use fire spells, all under the guise of "darkners are just servants, don't you think so as well, Ralsei?", which would end up again with him Firegraving someone.
Either way I'm sure that it's a really solid idea (if not done already by someone, which it probably was already).
"better to sleep"
There's a morbillion unfinished firetombs, if you check anywhere, to answer the question.