From what I've read here, I suspect you'd probably be good. Rotation will be a huge benefit in any case, and I think that you are right in looking at smaller animals for a smaller acreage. If you wanted, you could call your county extension office and ask what the typical carrying capacity of pastures in your area is. That number is usually given in animal units per acre, where "animal unit" is a 1,000lb cow. You can do the math up or down based on the projected weights of whatever animals you're looking at. Wikipedia indicates that Dexter cows are usually around 700lbs, so that would be 0.7AU.
The biggest thing is to be observant, both of the animals, and your pasture. I'm not sure who started it (Allen Nation, I think), but there are those in the regenerative livestock world who consider themselves grass farmers before anything else. Keep the grass growing and happy, and the rest will fall into place. I've been reading The Stockman Grass Farmer (a monthly magazine on the subject) for a couple years now, and there's a lot of good stuff there about pasture and animal management. They also have a free podcast, for those so inclined.
The grazing and rest periods are going to vary through the year, as weather, seasons, and animals change, so you have to develop an eye for when it's time to move, and when it's time to come back. It's both an art and a science. There's also an art form to multi-species grazing - working with cows and sheep and chickens and turkeys and pigs and ducks (or some permutation thereof), which can be beneficial, but you probably want to ease into that one at a time, so you make sure you're meeting the needs of each species as you go. I'm not sure that you could stack all that deeply on a small holding - it probably doesn't scale as if you're accounting for each animal individually, but you're still have to account some carrying capacity for each new animal, and if you overstock you'll end up wreaking ecological havoc and end up with a barren moonscape that will take a lot of time and rest to recover from.
As you practice and learn, you'll figure out just what your land is capable of, and with good management it will get better as the years go by.