I like your strategy of planting multiple tree varieties in the same plot. If you can keep the deer coming with a staggered crop you are on to something. That being said, if you have a high deer density and just a few of each tree, the deer will devour the fruit in short order.
I don't get an idea of scale in that picture, but if what you are trying to screen is the orange dot or the red/yellow x marks in the second picture you might consider building brush piles or stacking round bales of hay along that fence line or finger. It would serve as an immediate screen while your trees are growing and it could also be used to influence deer movement or create a pinch point. Brush piles are also a great habitat enhancement for small game.
I've also seen guys purposefully park old farm equipment and other stuff along fence rows, etc, in a way that served as a screen. If it is an active farm, deer get used to stuff like that.
Also, I know a lot of people walk that treelike, like your blue trail show, but if the crop allows for it or if it is your own land and you can leave a half tractor width or even less unplanted for a trail, I prefer to walk across the field. Yeah, I know, money/yield, etc., but life is about balance. Even if you spook deer walking in, they generally come back into the field after a few minutes because you aren't right on top of them. And because you don't leave a scent trail right down the woodline where they all have to come out (and often like to travel) they might not even make it to your trail especially early in the growing season when they usually browse closer to cover. If it is a taller crop, like cotton or corn, you are set for screening cover.
The plan is to plant new trees every year. I planted 10 this past year and look to plant 8 or more every year, this year going forward. It's just a matter of my wife giving me a certain budget every year and me having to fit my improvements within that. Might try growing some pines/spruce and maybe even apples from seed to cut costs. I know apples need to be grafted to retain their characteristics, but if it's for deer I don't think that will be necessary. I'm a green thumb so I have a lot of the stuff I'd need to do it. Might need to buy or borrow an auger from a friend if I'm going to be planting this many trees
I have 30 apple, pear and cherry trees I planted in an orchard closer to the home for human consumption and I've about had enough of digging holes with a shovel.
Everyone hunts around here a lot, so I wouldn't say the density is that high. The 10 trees planted right now should produce about 2500 lbs of fruit per year (average estimate) when they mature. For what I have planned long-term I'm thinking I can easily hit 10,000 lbs of soft mast within 10 years. Should be enough to hold a sizeable herd I think. I'm not worried about the summer too much, focusing 80-90% on fall and early winter crops.