Japan is like many other countries in the world..
There are parts of it that are beautiful
..or special for their uniquely cultural aspect..
And there are also some overcrowded cities…
So it depends very much on where you go. If you like big cities – you’ll find Tokyo and Osaka sublime. Cleaner than many other large cities, efficient and ample public transit, shopping galore.
If you want to surf and enjoy beaches go to Okinawa or Miyazaki-ken.
If you want to ski or hike mountains go to Nagano or Mt. Fuji.
You can also find sukebe old men buying girls underwear or teachers and parents who still believe in corporal punishment—but I don’t think this is unique to Japan.
Also, most importantly, please know that if you are going there as an American Armed Forces your experience will NOT be like that of someone living in Japan.
Living on base in Japan is like living in an American-flavored bubble. You have to go pretty far off-base and away from the surrounding areas (which cater to the bases) to get an authentic experience.
There are 3 major areas you’re likely to be stationed: Okinawa (highest likelihood), Yokohama (esp. if you’re Navy or Air Force) or Nagasaki.
Please know that Okinawa is NOT like the rest of Japan. It’s like visiting Hawaii and saying: “Oh, so that’s what America is like.”
Okinawa is wonderful, beautiful place to live (I lived there in High School)..but it is a pan-Asian melting pot that is HEAVILY influenced by the large American military presence on the island. You could be in Guam or Okinawa and not really know the difference, IMHO, as far as being stationed on a military base goes.