I would say Shinto. It gives her a lot more range with her projectiles, though I haven't played around with the others as much and I'm just going with what's best for my playstyle. I can't really see her as rushdown enough to use Buddhist faith, especially since her dash isn't really the greatest for getting in (though her teleport is pretty good).
Taoist faith don't think is for her, she doesn't really need fast projectiles and from what I've tested it doesn't affect how long it takes for her projectile declare to come out any quicker.
Yeah, I would agree that having your projectiles going farther with Koishi would be better. More range on her projectiles means her spells will activate farther away I assume. I myself am trying to find my favorite Mamizou Playstyle. I use shinto right now because I like having some range, but I kinda liked Taoist as well. Buddist could work if I get more of a rushdown style for her. I just need to hit the training room and work. It sucks that you can't change spells in training...
Usually I would rather a game be delayed for months and actually finished, but you're right that they didn't have many options because of the convention release. Again, very happy with the pace of the updates, just as long as they're not thrown together and cause more problems than they fix. I hope they'll release a fixed version of the game disc once everything is ironed out, but that seems kind of unlikely.
I think the last patch caused issues since they had no time to test. this latest one they had time to test a bit. I think we will not see issues like that again
I doubt they will release a fixed game disc version, mainly because that will cost them a lot of money. I do hope they make an online store where you can buy the game and download it with the updated versions. I did buy my own copy, but being able to download it will help a lot of people.