He's the one who contracted Frieda you have to remember that she won't be there officially till her coming of age ceremony
Also they lent Damuel the money that's the reason why he was working with the high priest in his office in part 2 to pay off his dept
the official LNs translation has all instances refer to them as red pandas (which is why i probably never connected Lessy XD) but whatever. i was just wanting to point it out since i think most ppl would recognise it as such
small detail the animal that mynes highbeast is moddeled after is more known as a red panda. (yes it can also be known as the lesser panda but most ppl know it as a red panda due to the innacuracy of the description)
he would in a heartbeat if they were located in an area with a bit of a warmer climate where fans would be needed though he'd probably use them as actual fans XD
the anime didn't mention it and it wasn't revealed in the LNs untill much later on it was first initially revealed in one of the fanbooks when ppl were asking wether the reason why benno knew so much about the devouring was because of his lost love.
the high priest and the high bishop aren't one above the other necesarily (at least when their families are of the same status) they are both one above the other in dependent on the situation. However all blue priests and shrine meidens are below them. As you stated the high priest Handles day...
Ferdinands head gray priest (he was the one that delayed myne meeting with Ferdinand when she was running around in the temple away from the toad right before the final fight of part 2). he had a lot of other problems but i don't remember all the things that happened nor how many the manga...
a lot of answers to the questions you posed here are explained later on but so far as what was already revealed.
yes the church is just another magical institution. they are responcible for providing the mana necessary to the duchys harvest during the winter ceremonies in the chalises then those...
when it comes to family trees the official ones can be found in the 2nd Fanbook for the LN found here in digital format https://j-novel.club/series/ascendance-of-a-bookworm-fanbook