What are you planning on saving

Sweet rocket and honesty I am hoping to save. Possibly pansy antique but they are F1 so will be a selection program for the future, that is if I like them.

Yet again I am growing golden sweet and shiraz mangetout so I can create a hybrid (grown the plants before but never got round to crossing them) and hopefully get red mangetout

As for everything else it depends on what grows.

I'm having another go at leeks - I had one successful year but then I lost all of those plants to leaf miner.
Otherwise the usual suspects, cosmos, sweet peas, dill, zinnia, honesty.
I have white and purple honesty - will they cross?
I might try tomatoes for the first time, if we like any from the Kokopelli mixes, especially if they don't cross,

Thank you Veggie - I didn't know tomatoes don't cross! I've read that guide before, and as most of the veggies in that guide do cross, I must've not realised that tomatoes are not one of them! That's very good news - I'll save more tomato seeds now

There are exceptions to the "tomatoes don't cross" rule so its not 100% but most toms are OK.

... I'd like to save some beans, but I'm growing quite a few varieties, so it may be hard to keep them separated.

French beans don't tend to cross. I've been saving 3 different one for years without problems. Runner beans do cross though.

I'll be saving peas, french beans and broad beans as usual, tomatoes chillis and probably leeks (there are a few big ones now developing flower stems).. I've got seeds of onions, capsicums and a butternut from last year that should still be OK next.
Also though not seeds, potatoes and garlic. I always save the biggest garlic bulbs for resowing.

I'll also save some sweetpea this year if I can persuade Chris not to deadhead so thoroughly.