Welcome to the club! You can read a bit about my experience so far on poor draining soil with a variety of trees.
#1 - PROTECT those trees! You will need fencing for deer as well as rabbit/mouse protection. You could probably just add a couple posts to your existing fence and add wires with flags at 8’ to keep them from jumping over. Trunks can be protected with hardware cloth or spiral guards. Sunburn protection by painting with latex paint (Painting trunks for sunburn and rodents - #41 by clarkinks).
You don’t say what your solar orientation is. I am hoping that your backyard faces north because the shadow those big trees will cast will limit how some of your fruit will ripen.
What root-stocks did you use? You will want something with crown and collar-rot resistance.
Consider also planting some grapes. Backyard grapes are so much better than store bought.
Finally, don’t worry about planting too many trees. Order some scion wood and start grafting this spring. Apples are super forgiving and you can easily have 3-4+ varieties per tree. A mature tree will give you 70+ lbs of fruit each and I prefer to have 20-30 lbs of several different varieties maturing at different times over a 4 month period than a huge amount of 1 type ripe all at once.
Have fun. Experiment on what works for you, in your soil, in your climate, in your hands, for your taste-buds. People can give you guidance but until you actually try it you can’t be sure.