I have never owned an 11.1 Detroit. My statement was based soley on information I got from truck drivers and from trucking forums. Same type of deal as you get with Chev/Ford arguments. Some like this or that, and others don't. It sounds like you are happy with your truck, so I wouldn't worry about it.
The thing I don't much care for is the 4:33 axle ratio. If you ever change it, (probably not worth the expense) I would reccommend a 3:42 or 3:55 axle ratio to go with your OD transmission. Your fuel mileage would increase by at least one MPG, and you would cruise at lower engine RPMS. Pulling power would not be affected.
I reccommend that you bite the bullet and fill those fuel tanks. Then refill everytime you get down about 100 gallons. The more empty space you have in the fuel tanks the more condensation you will have mixed with your fuel. I add one quart of ATF to each 50 gallons of fuel. This improves lubricity, improves fuel mileage, and helps keep those injectors clean.
Just my two cents,
Larry