Anyway, OP as Waldin el Greco in his van suggests in post #2 there are 101 (like the airborne, see what I did there) sites and sights telling you all about the D-Day beaches, so you'll find something to suit you. After all, you've found the air shows.
The most common mistakes bods make are:
1. Not realising that from one end to the other of the invasion beaches is a bloody long way. Not surprising maybe when one considers that no less than three armies had to be landed.
2. Refusing, out of some weird pride, to use the motorways. Instead, they trundle along the (not very exciting) roads and waste time. Only then do they look at their map to realise that Pegasus Bridge is nowhere near Omaha Beach, so they are not going to have time to see the airborne museum that sits next to it.... And see the (very excellent) Bayeux Tapestry that afternoon.
Get yourself a good map and mark the positions, working out how best to spend your time. You could spend two minutes looking at the remains of the Mullberry Harbours or 30 if you are really interested. That's 28 minutes potentially gone or saved out of your looking time at the battery at point XYZ or ABC.
Hotels / digs / B&B's? How many do you need? It's tourist city. Or if not tourist city, at least tourist town. My suggestion might be to find a hotel / squat / digs / wild camping spot / ditch as a base somewhere near the midpoint of the beaches, viewed east to west. If you chose a spot at one end, it's a long schlep to the other and back again. See point 1.
You'll work it out, I'm sure.
PS Lots of bods like the British run B&B's.... They know why.