Don't worry about it being up to Disney standards, the Tokyo parks far *exceed* the standards of the US parks. Tokyo Disneyland Park is Magic Kingdom, take 2. The imagineers learned from Florida and fixed their mistakes, meaning the Japanese park is a perfect blend of Anaheim and Orlando's parks. And as for DisneySea... words can't really do it justice.
Others have covered many of these points I think, but my tips would be these:
Familiarise yourself with the park map and what attractions there are before you go, or at least plan what to get Fastpasses for.
Make good use of Fastpass while you can - they run out quickly, and have long lines just to get them, but those lines move quickly. This is a good article on that side of things:
http://www.themeparkinsider.com/flume/201308/3624/
Try to pick a weekday to go, and get there before the park opens, as weekend crowds are insane. Also lots of people arrive in the evenings, so don't count on lines getting shorter as the day goes on.
At DisneySea, Tower of Terror and Journey to the Centre of the Earth are the big things to go for - get a Fastpass for one, then ride the other. Luckily Toy Story Mania absorbs the main Fastpass rush, but I suggest skipping that as it's no different to the USA versions.
DisneySea must-do's are Tower of Terror (different to the USA versions), Journey, Sindbad (don't miss!) and Storm Rider. Oh, Fortress Explorations is Tom Sawyer's Island to the max. Oh, and 20,000 Leagues. And Aquatopia. Their Indiana Jones too... And the shows... oh there's just so much good stuff.
Also if lines seem long for everything, don't despair. There's always quiet corners and so much detail and things to look at. You could spend an afternoon in American Waterfront alone - make sure you go inside the ship, it's stunning!
Have a great time, take in the detail, don't panic if crowds seem insane, and most of all just enjoy being in the most detailed, cared for, and expensive Disney parks you'll ever set foot in.