Re: rotating tomato plants–or not?
Crop rotation on a three-year basis is the general recommendation, particularly if diseases that can overwinter occur (which late blight cannot in the North, but many other things can). That said, who has the room? :) I try to rotate at least every other year, swapping which raised bed(s) I devote to tomatoes and putting my garlic or brassicas there instead in any given year. I also add lots of compost each year.
I would point you to my pretty good selection of tomato stories on the blog, which include ones about tips for success and also what to do about disease issues: