Hello Maralyce, welcome to Canadia-land! 
Our guild sounds like the perfect fit for what you’re looking for! Our guild is an 18+ guild, most of us are in our late 20s to 30s. We have quite a few achievement & mount farmers, myself included! We host Fun-Runs: achievement runs, mount/transmog farming runs. We host a variety of contests & events everyone in our community can join in on!
We raid Tuesday/Wednesday 9pm EST to 11:30pm EST (server time), I hope these days and timeframe could work for you!
Would love to chat more!
Neithia#1315
Please check out our forums post for more info on our Guild!