I am also doing yellow beetroot, I'm not keen on the purple/red stuff as it is just too..well, purple.
Also i'm trying courgette 'Zephyr' which looks like a pale green courgette that's had its end dipped in custard.
I'm also trying celery, even though I've had very little success with celeriac, and I'm giving that one more try as well.
Also swiss chard, the plain white kind.
I have double the space this year as i have just moved to a full plot, so can afford to experiment a bit more.