the squash vine found its way out of the bed (through the deer netting that surrounds it!) and out across the patio
I wanna see a picture of this.
I have similar concerns about things getting shaded out. In addition to things that benefit feom the shade, planting early spring crops BEFORE the tomatoes and planting the tomatoes between THEM works since they will be harvested and gone by the time tomatoes need the room. Same with garlic planted previous fall and tomatoes planted between them in spring.
Pole and runner beans have worked for me because they find their way up above the tomatoes. But you need to choose varieties that won't be so vigorous as to overwhelm the tomatoes.