I would suggest moving slowly and only planting a small number of trees initially even if you ultimately plan to have an large orchard. The initial trees will give you a good idea of local disease, insect, and animal pressure. Based on the experiences with these trees you’re going to be better equipped to pick good cultivars and rootstocks that will prosper under the local growing conditions.
Are you planting a hobby orchard or are you mainly planting a orchard that produces a crop you want to sell? Your answer to this will change what you should plant and how you manage the orchard.
I would also suggest doing as much research as possible before you plant anything. In your area it may be possible to grow apples and pears organically. But only if you have trees that have high resistance to local diseases and you are willing to bag apples and pears or spray Surround (a type of clay) to protect the trees from insects. Peaches and plums have problems with brown rot… it’s highly unlikely you will be able to grow them organically.
The county extension will have some information but their expertise may be limited if you are in an area that fruit trees aren’t commonly grown commercially. Pollinators will probably be ok at least initially. There are rules dealing with grazing animals under fruit trees so if you intend to do this on a commercial basis you will need to look into this.
I would take a look at this thread.