Re: It's getting annoying..
From your post, I see two issues. The first is "getting exercise," for which there are plenty of solutions. Done right, aikido isn't great as exercise anyway. Join a gym, study another art, go running with your dog, whatever.
The second is that you feel like your own training is suffering because you're working with beginners all the time. For that, I agree with the consensus. It's a different kind of training, sure, but beginners have a lot to teach.