G's D are ones you need to support. A good tried and tested cherry variety, tasty and well worth growing.
Since I lost all my plants to blight two years ago, I have been growing blight resistant ones along with others,
just in case! (I also disinfected all my pots and bought new canes post blight disaster. Hmm but did the canes get thrown away? I have a nasty feeling that new gardener kindly gathered them all together in one big pot

)
Pat, the complication re the tomatoes is that they are (or will be) on the Quadgrow system, so raised a good 8 inches off the ground. (This also makes them falling over more of an issue.)
I will look into your support system though. It might be adaptable. I bought some frames that go around the whole quadgrow thing, at considerable expense. (Could only afford three, so need ideas for the other two.) I am not at all confident that these will work, so intend I to weigh them down with 'sand' bags too. The best option would be if I were growing them on soil/grass. I could then peg them down with some sort of homemade thing, but alas they are on (uneven) concrete slabs on my patio (best place for sun.) I may also put terracotta balls on the top of the plants (not sure I have enough) to help prevent evaporation and weigh down a bit more. (Although that will make a mess if they do fall over!)
OI suppose the quadgrow system might be more stable if it were configured as a square rather than a rectangle, but that might encourage disease, I suppose...?
I can't comment on side shoots

I know what you are supposed to do and I do remove them, but not assiduously. Nor can I bring myself to remove growth after the formation of the fifth truss... Maybe I should experiment this year. Would I get more fruit with fewer leaves? I was struck by an image of someone's tomatoes on the GW forum (can't find it now) of a tomato plant heavily laden with fruit, but not my foilage.
Meanwhile, some of the fruit on my early Gardener's Delight plant (the one above with bleached leaves, are finally beginning to ripen.

The potatoes I tried to grow in bags last year are still in them

I got fed up. Slugs kept eating all the leaves. I might get a crop?!
“In the midst of winter, I found there was, within me, an invincible summer." Albert Camus