Garden lockdown!!

I'd grow only seeds that I could save seeds from - no F1s.
I'd learn how to save seeds from cucurbits , especially, courgettes, cucumbers and squashes. I'm OK with beans, peas, tomatoes and lettuce and kale.
I'd concentrate on making more compost which also produces the leachate that I use to feed the plants.
I'd propagate "easy" plants from cuttings like herbs, perennial kale, soft fruit to swap.

Overall, I think I could do it - so I might give it a try.

Isn’t that pretty much what you do anyway? 

Almost, but not quite!
I have grown some F1 cucurbits this year as I've been using up old packets and, since I've no idea which is which i won't save seed from them. The cucumbers are labelled but I need to isolate them from the others so that they don't cross. 
I need to sow more beans as I don't have enough growing to eat them and save seed. Same with mangetout.
Need to use the compost bins in the garden better - instead of just using them as rubbish bins, I need to be more proactive with them - adding browns and aerating them.
I haven't bought compost for a couple of years and still have a stack of coir boxes to use. I've been reusing the old compost from the GH beds, with added coir and Hotbin compost. Seems to be OK - the tomatoes and cucumbers are thriving. 
I could propagate more cuttings than I do - as I tend to only grow more when I need them, not with swapping in mind.