Hi, I'm a christian at Bangor and although not part of the CU I have friends who are and have been to some events (both official and just get-togethers with friends who are very involved with the society). Out of the people I know in the CU two are lgbtq+ (although there's probably more to be honest), I would say out of them one is visibly queer, and I've never heard her speak of feeling uncomfortable in the society. I've really only ever got the impression that it is a very friendly and welcoming place. As you said there are always a few funny ones, but I've found that Bangor is generally very inclusive, with a high queer population, and the SU are really good at dealing with issues within societies. They've also recently created a mandatory wellbeing/inclusion role for societies, I'm not really sure what they actually do 😅 but seems positive anyway.
There are also loads of different kinds of churches in Bangor depending on what kind of thing you're looking for. Personally I had issues at one of them, where I felt kind of uncomfortable being there as a gay person, but bc there are quite a lot I was able to find another church. So now I attend Mosaic evangelical Church which I found welcoming immediately. Everyone is so friendly, and there's a lot of students there. So if you usually go to an evangelical church then I would 100% recommend. Only downside is it's more of a trek to get to than most of the other ones 😅 but bonus - there's often free food.
Sorry that ended up a bit of a long one but I hope it was helpful. Also one last random thing - sometimes they have bowls of pin badges in the SU reception.So if you like freebies...I got a really cool pride flag and a slightly less cool (but still nice) pronoun pin last semster hahaha