Sorry that I have not answered your post before now!
Here in SA that container you describe for your beans being rectangular and longer than wide we call a 'planter' and I have quite a few. I find that with space restrictions, a person can get more action going for many reasons and they are easy to manoeuvre and access and care for in a way. If I have understood you correctly, then it should be as deep as it is wide and twic or three times as long. It is time to do another article on a vegetable so I will be writing one for you very soon on beans.
I grow chives with my carrots (or marigolds in the ground) and am one of those who thinks that the chives (or shallots) for some reason give the tomatoes a beter flavour! Still it's just taste and no proof really. In terms of radishes, they are quite strong flavoured plants and I prefer to grow them on their own and again I would not grow them with carrots, these two are not the best of pals and radishes tend to inhibit carrots from full growth. Again it is just what I have found so I would be interested to hear how your carrots get on and if they do grow full length and not stubby like mine did... mindyou, stubby carrots come from a lot of other reasons (like the wrong soil, stones in the ground and incorrect watering).
But that having been said, it seems that you have your work cut out for you and a nice choices of growth and colour and herbs veges and flowers and alternative plans. I have not really been lucky with my dahlias, so if you have any tips to pass on I would like that, I don't know, there are so many varietals, such beauty in dahlias (I particularly like the spidery one and also the tiny pom poms) but any that I have planted just do not perform for me. Maybe it's my feeding? Dunno.
Guess you like pasta! Pizza? Pesto anyway.
Thanks for telling us about your garden, appreciate it. And P S your hierloom tomatsh should taste as good as they look!