I'm still learning. This is my 3rd season. My first setup was only a cheap 3 foot x 3 foot raised bed kit. Divided it into 9 squares, and grew leeks, onion, parsnips and carrots. 16 to a square foot! Had an outstanding yield of veg! All well formed stuff. Problem last year was the amount of variety I grew, large stuff next to small. Things got shaded out and died. That's why it's simple this year. I will post pics as it progresses but I've got a good feeling this year.
As space seems to be a problem have you any room for tubs containers etc round the patio /garden. Try beetroot spinach sa