I like to put a 'cage' or stake to guide the tomato plant onto before it gets too big. Usually around the time it starts producing fruit, it's time to support the limbs.
My zucchini and squash are all bushy plants, I've never seen one that was a true vine. They pretty much take care of themselves, I've never worried about dead blossoms or trimmed back any leaves. Why do you trim back the leaves? Might not be good to let too much sun hit the fruits.
I water the tomatoes deeply every other day, the squash get water every morning. As the heat picks up here (FL), I will water the tomatoes every day, too. I mulch with oak leaves, which helps keep the roots cool and the weeds down.