1 I wonder if male applicants wear the same outfit. This reminds me of the wing bells in Haibane; they were really cute on the girls, but I bet it drove the boys crazy.

"Gods of education". Huh. The Greeks only managed a goddess of wisdom; as far as I know, they never thought to worship a god of education. I wonder if there's a translation hitch, maybe something to do with honorifics?

The Grand Master Lelei came to see is completely dotty, sort of like her own Master (who was a dirty old man). I wonder if there's something about Mastery that sends folks off the deep end.

Three "I wonders"; that's probably enough.

2 Hypothesis: In order to do magic, you have to use  your brain in ways that are different from the way you use it for... actually thinking. The better you get at that, the battier you get. Eventually you get so good at doing magic you're a drooling idiot.
Unless you go the apostle route, which protects you somehow.

3

In the manga Master Cato isn't a lech and isn't nutty. That's something they did in the anime.

I'm sure that male applicants wear something similar but not identical.

As to the Gods, when apostles finish their thousand year apprenticeship and become gods, they get to pick what they want to be gods of. The only limitation is that no one else already has it.

Apparently these two decided to become gods of education.