Did you get your orchard planting started? Just curious what your goals were, just food for the homestead or for sale as well? I started planting my "Permaculture Orchard" in 2015 and am continuing to graft and plant - as my resources are limited I have grafted/propagated almost every tree, berry and support plant myself. Our goals were to provide all our fruit needs year round (including sauce, canning, dehydrating and root cellaring) and we plan to have excess to sell in a micro fruit CSA in a few years. All in all, the orchard area is ~1/2ac and this includes a ~12' tall mixed, fruiting windbreak on 3 sides. This spring I'll be grafting out the last of the trees to transplant into the orchard in 2018 - a four year process, which is slow but the time allowed me to solidify my goals, do the research to track down and acquire suitable cultivars. I went with semi-dwarf trees, about 50 in all with a (16x12' spacing), mostly apple, lots of plums, pears, some peaches, tart and sweet cherries, pawpaws, with 8-10 mixed trees per ripening window. My rows are laid out 1=-Jul, 2=early Aug, 3=late Aug, 4=early Sep,5=late Sep, 6=Oct+. Windbreak includes tons of stuff from juneberries, hazelnuts, elderberries, seaberries, etc. Understory has many support plants, herbs and currants, aronia, raspberry, blackberry, strawberry, etc. I did not include NFTs in the orchard design but have (or will have) a coppiced NF shrub adjacent to each fruit tree as well as alleys full of red/white/sweet clover, alfalfa and other herbaceous nitrogen-fixers which are mowed and mulched in the row. The alleys are also tractored by layers and broilers in during the growing season. I keep nut trees, persimmons, mulberries out of the orchard area for size reasons (and apricots on the N side of the house to delay bloom).
If you are planning on such a close spacing, please get appropriate rootstocks! Otherwise you are battling vigor and the natural tendencies of the trees and will spend a lot of time in summer doing size-controlling pruning (winter pruning typically increases vigor). I'm too busy in summer to mess with that. If you have reasonably good soil and water/water-retention semi-dwarf rootstocks should be pretty self-sufficient (I do not irrigate my orchard, though I do mulch and have watered individual trees a couple of times during dry spells in the first 2 years). Also, if you plan on being "organic" you better be "holistic" (see Michael Phillips The Holistic Orchard
) with fruit trees in the high pest- and disease-pressure Midwest. Look to varieties with natural disease resistance. This is NOT no-spray, but management-intensive "holistic" sprays of compost tea, milk/whey, fish, seaweed, neem, Surround, etc. I believe you have to address pests and disease on multiple fronts in our climate and that definitely means addressing soil mineral balance for maximal nutrition/high brix, walking the orchard daily, and spraying every 7-14 days or so during the season, probably setting some pheromone and sticky traps. I use a 4 gallon backpack sprayer for my 1/2 acre about once every 10-14 days, though as the trees mature I have a feeling multiple passes will be required to fully coat all trees).
Definitely learn to graft if you haven't already. Such a valuable skill that I left out of my "homestead toolbox" for too many years but it is easy and opens up a world of possibilities. Also check out North American Scion Exchange https://scionexchange.us/
and Growing Fruit http://growingfruit.org/
websites for forums and scion exchanges.