Although I enjoyed it, I thought the same thing. I echo votes for the National Infantry Museum. The Airborne & Special Operations Museum in Fayetteville, NC, is awesome. The West Point Museum, West Point, NY is also very nice and you can tour the Academy, which is pretty cool. The National Naval Aviation Museum in Pensacola, FL is nice too. Two more, the Mighty 8th Air Force Museum in Savannah and in Charleston Patriots Point Naval & Maritime Museum has The USS Yorktown, a WWII sub, a destroyer, and a VN river patrol boat base camp.
I need to check that out one day. That sub by the Yorktown is awesome. When I was going through it some guy I guess knew where the dive alarm was and scared the hell out of everyone on it.
I took my two boys on a road trip last summer. We visited the Air Force Museum in Dayton and it was great. Both boys had a great time and the variety of equipment is incredible. We especially enjoyed the UAV's hanging from the ceiling.
On the other hand, we also stopped at the Patton Museum at Fort Knox, KY. I received my armor crewman training there in 1977 and I have fond memories of the museum and their annual 4th of July battle reenactment. But the Army has moved the armor collection to Fort Benning, GA. They do still have the Patton staff car and the revolvers. But that awesome armor collection is gone. Unless you have a burning desire to see his car and pistols, don't bother. They had maybe 3 AFV's on the lawn and the inside was being remodelled into a Leadership museum. No foreign armor.