Hi Lonestaar,
It seems like Supercool Discothequ could be the casual guild you are looking for. We run Mythic + groups in the week and raid on a Sunday night and we would love to add a priest to the raid team. Please add me wolfus#1389 if you would like to have a chat.
If you want more information please check our our post: [A] ghostlands-dragonblight <supercool discotheque> Casual 1-night-raiding