I wouldn't try to design a property around stands. I would try to offer a variety of things to the deer and see what they like/use. You can always add/move stands and blinds. Like Bill said, just keep tweaking it.
I disagree. With a tiny property, the only thing one can really accomplish realistically is improving the hunting. From my perspective, the primary consideration would be stand location. I'd first look at prevailing winds. While i do use a lot of permanent stands/elevated blinds as I'm getting older. I find deer quickly become leery of them. I shot a doe out of an elevated box blind the other night with a muzzleloader because my rifle had failed and was in the shop. Two does came out into the field. The stood like statues ears cupped focused on the blind. They stood just looking and listening for over 5 minutes. Who knows how long they had been watching that blind before stepping out. They kept their distance at 50 yards (fine for a rifle or muzzleloader but not for archery). I waited until the leading larger doe finally put her head down. When a pulled back the hammer on the muzzleloader there was a soft click. She immediately went of full alert, stared for about 15 seconds, then headed back into the woods. She stopped short but was behind a tree cage at that point. They were both so nervous this late into the season and I had a shot at the smaller doe, so I took her.
The point of that story is the blinds, temporary or permanent, can become immediate targets of deer senses once they learn danger is associated with them. That doesn't mean you won't ever get deer close to a blind, but the more hunting pressure, the more wary they become of blinds. Temporary blinds draw similar attention, not because they are associated with danger, but because the are new and out of place.
So, I preferred mobile tree stands like climbers when the situation allows and when I was young enough to use them comfortably. From the pic, it looks like the top left corner might allow the use of treestands. So, the first question I would ask myself is whether the prevailing wind will allow for regular use of that corner for stands. If so, that would be where I would start. Short of fencing or much more dramatic terrain, it will be hard to funnel deer past a specific stand location. However if the top left corner works for a stand location, trying to create a property design that allows me to access that corner without spooking deer and generally moves deer toward that corner.
Again, I'd probably just let nature take its course allowing most of the 20 acres to get thick and ugly. I'd probably strategically bushhog some paths through it and put a small food plot near that upper left corner provided the prevailing wind allows it to be the primary general area of stand sites. I would not try to uses food as the primary attraction. Rather I'd let cover be the primary reason deer use your land. A low maintenance crop like clover is a good candidate. Less human activity the better. When farm crops are harvested it may provide some attraction, but more importantly, if deer are bedding on your 20 acres waiting to feed on the big farm fields after dark, a tiny field that feels secure close to bedding makes a great appetizer during shooting hours.
Thanks,
Jack