I'm leveling a tank because

Accurate but why would I want to tank in a guild that doesn’t take me to gruul/mags? personally I wouldn’t tank for a guild unless I had a guaranteed spot in the “main” raid.

How we solved this in my guild is that every tank we have is expected to have at least two tanking toons and tank two Kara’s a week for the guild, that gives us a 6 runs to work with between 3 tanks in the guild. We just recruited a 4th tank today and i’m pretty confident he’s going to leave in a couple weeks because we just don’t have a gruul/mag spot for him unless we make a second gruul/mag raid.