I've done my grade 8 bassoon and am looking for some pieces to play. What would you recommend? (I can't stand anything by Mozart so please don't recommend anything by him)

You could give 'Flight of the Bumblebee' by Rimsky-Korsakov a try.

If you haven't already you could have a look at some of these pieces which are a fair bit different to Mozart: Solo de Concert by Gabriel Pierne, Sonata for bassoon & piano by Arnold Cooke