I've had a loft the same size for the past thre years, only just extended it by 6 foot. I had it divided into two sections one with perches and one with nest boxes. No stock birds, with so few they all have to fly !
You can still compete, put the hens in with the young birds and race the cocks widowhood or fly ntural. Both ways work.
Main thing is with a small set up, don't think you can enter every race. Plan your season and stick to your plan !