Generally in a crop rotation you want to follow a high nutrtient user with one that helps rebuild the soil, ie. Corn followed by soybeans. Your rotation is all nutrient users with no nutrient replenishers (legumes) in the mix.

I have separated the families into three categories; High Feeders, Low Feeders and Negative Feeders. I use the need for nitrogen as the basis. Thus, corn and potatoes are considered "High Feeders," Tomatoes and peppers are "Low Feeders," and Beans and Peas are "Negative Feeders." I rotate these by planting a "Low" feeder where last year (or crop) was planted a "High" feeder; A Negative Feeder where last was a Low feeder and a High feeder where last was a Negative feeder. Thus, a High feeder takes a lot of nitrogen from the soil, so a low feeder, not needing as much nitrogen will do just fine. Then a negative feeder to replenish the soil for the next high feeder. This way I do not plant the same family in the same plot but every three years.

Of course I need to keep the rest of the nutrients up using compost and cover crops where needed.

Thanks to you both for the information. I will keep feeding/nutrient demands of plants in mind, and plan for legume covers, as I'm working out the rotation scheme.

My main question is whether the plant's order should also be a consideration in a rotation scheme. Here in Florida soil diseases & pests are a major concern. My plan is to group plantings by family--all the nightshades in one bed, all the aster family (lettuce, chicory, etc.) in another, and so on. This way I can keep the rotation scheme neat, and if everything works out, a bed will get a five or six year rest before it gets planted with the same family again.

But in summer I sometimes plant things like malabar spinach and purslane. These are in the same Order as chard and amaranth, but in different families. I also use buckwheat here and there as a trap/cover crop. This is also in the same order. I realize I need to plant a legume after something like chard, but would the following summer I plant malabar spinach there? Are they closely related enough to matter?

I have a small garden, and sunny, back-of-the-garden type tomato spots are in very short supply.
If I could, I'd rotate the Solanums properly, but I don't.
The other thing I move around not just for feed requirements is carrots, to try and avoid the next generation of carrot fly.
Aside from that, I do it by food requirements (and water, to an extent) rather than family; I mix my plants up so much, there's no way I could maintain a rotation!
For example in a 'heavy feeder' bed I recently broadcast radish, beetroot, cabbage, broccoli, a few types of lettuce, coriander, spinach...
a zillion random things came up too.

Bill, my experience in florida sand is that a lot of legumes in the rotation is critical. I am finding that velvet bean, short-season pigeon pea, lima, and climbing cowpea are all very good and very low maintenance. They can all handle the summer climate. If you need a winter legume you can use fava or english pea.

Regarding nutrient "user" vs "rebuilder" I fail to see the relevance if the crop is being grown for mulch or compost. Also, this is the first time I've heard of tomato/pepper classified as light feeders. I would agree that they are less hungry than corn, but not light feeders.