I have the same problem my wife likes to put expensive bourbon in coke and her steak well done. So my solution is to cook two steaks one an inch and a half thick the one inch thick. It works we have been married over 50 years. I ain’t perfect either
I have never covered a grill except in winter. You do have to protect the 590 from rain but I have found covers generally cause sweating. Moisture from humid climates tends to condense inside the cover. That plus the heat promotes rust. I recommend just hosing it off from time to time.
However...