@rogercooper Thank you so much. I plan on doing a version that is not uhd if that would be cool.

@rogercooper This mod is now available in the in-game downloader.

Fleet building (Axis)

Battleships (70 points or so)
The Yamato (70 points) and Musashi (66 points) give you the most brute power of any ships in the game. They're a little weaker at anti-air than the Iowa. Also they only have extended range 4, instead of extended range 5 for the Iowa. Nevertheless these ships are an outstanding way to provide surface combat power.

Battleships (50 - 55 points)
You have some good options here, including Japan's Nagato, Germany's Bismarck, and Italy's Vittorio Veneto. Ships at this price point generally have extended range 4. Good overall stats, making them strong at surface combat.

Battleships (40 - 45 points)
As with Allied battleships, Axis battleships at this price point tend to decline a bit in power, as compared to their more expensive counterparts. Weaker armor, making it easier to score hits on them. Weaker main guns, making it more difficult for them to penetrate the armor of the game's heaviest units. But you're still looking at powerful units here.

Battleships (below 40 points)
Some interesting Japanese options here, as well as some battleships which aren't Japanese. The things I wrote about the Allied battleships at this price point apply also to Axis battleships.

Cruisers
Japan has some interesting options for cruisers, especially considering the long range of their torpedoes. Torpedoes ignore armor, allowing them to inflict damage on any surface ship. However, cruisers are more vulnerable to surface guns than are battleships. In fact, cruisers are more vulnerable in general than are battleships.

Destroyers
Axis destroyers are broadly similar to their Allied counterparts.

Aircraft carriers
Japan has some very good options with respect to its aircraft carriers. While its carriers apply various types of bonuses, they are especially good at providing bonuses to torpedo bombers. Or, you might choose a slightly less expensive carrier which provides fewer bonuses.

Aircraft
Assuming a cutoff date of 1942 or earlier, the Zero is a reasonably powerful fighter, at a good price. The Val is a good option as a dive bomber. But where Japan shines is the Kate: an excellent torpedo bomber. Not only is the Kate good at attacking heavily armored ships, it can also provide anti-sub war if that's something you need. Considering the bonuses Japanese carriers often provide to torpedo bombers, it's as though you're being warmly encouraged to build at least some Kates. Not that there's anything wrong with including some Val dive bombers into your unit mix. As for patrol bombers: you have some good Japanese options, such as the Betty. Also some good non-Japanese options, like the German Kondor.

Subs
Japanese subs are often a bit more powerful than their American counterparts. But, their price point reflects that.

Some thoughts on fleet building (Allied)

Battleships (70 points)
If you're the Allies, you have one option here. The Iowa. The Iowa has the best main guns and armor of any Allied battleship. Also the most hull points. In general, American ships have slightly better anti-air defense than their Japanese counterparts. That's certainly the case here, with the Iowa having better antiaircraft fire than the Yamato. Also the Iowa is the only ship in the game with extended range 5. When undamaged, its main guns have a range of 5. After taking damage, its maximum range is reduced to 3.

Battleships (50 - 55 points)
Some good options for the Allies here, most of which are American. There are also some non-American options, such as the French battleship Richelieu or the British battleship Rodney. Battleships at this price point will generally have extended range 4. When undamaged, they have a range of 4. On taking damage, their max range is reduced to 3. In general, battleships at this price point are like slightly weaker versions of battleships at 70 points. 5 hull points instead of 6, for example. A little less armor, making it a bit easier for opposing units to land a hit. A bit weaker main guns, making it a little less likely to land a hit of your own.

Battleships (40 - 45 points)
Also good options for the Allies here. A number of which are British. In many cases the British battleship will have something wrong with it. Slow 1 or 2, which can reduce your movement speed for a turn depending on die roll. Fatal flaw, making the ship potentially easier to destroy. Stuff like that. But these are still powerful ships, and at a lower price point than above.

Battleships (below 40 points)
As the price of a battleship continues to decline, it becomes in some ways less like a battleship and more like a strong cruiser. More vulnerable to damage. Less able to use its main guns to inflict hits on heavily armored opponents. But ships at this price point still have their uses. They're good at attacking weaker ships. Also, any surface ship can take an objective, or deny an objective to an opponent. There's always the chance of getting lucky, and using your main guns to inflict damage on even a heavily armored enemy. That chance increases as you reduce the range.

Cruisers
It's probably not a great idea to use cruisers as your counter to enemy battleships. But you can still use them to attack other enemy ships, such as cruisers, destroyers, and carriers.

Destroyers
These are useful against subs. Also they can have torpedoes. Torpedoes ignore armor, which means they can inflict damage upon even the most heavily armored of battleships.

Aircraft Carriers
If I'm building an aircraft carrier, the three things I most want to know are: how much does the carrier cost? How many planes does it hold? What bonuses does it provide to planes? Most Allied aircraft carriers are American, and American carriers trend toward providing bonuses to dive bombers rather than torpedo bombers.

Aircraft
For aircraft I'm assuming a cutoff date of 1942 or earlier. Four different categories of aircraft from which to choose: fighters, dive bombers, torpedo bombers, and patrol bombers. Of those, patrol bombers are strictly land-based, whereas the other three types can be based on carriers or on the land. You're going to want some fighters. These will help fight off enemy air attacks, while occasionally killing enemy aircraft outright. As for dive bombers vs. torpedo bombers: you have good options for both, but you might be better off emphasizing dive bombers. Especially with bonuses from carriers, American dive bombers have the ability to inflict damage even upon the mighty Yamato. That said, torpedo bombers can play a good role as well. The U.S. and Britain have some good options for patrol bombers. Often, the patrol bombers available to you will be inexpensive, capable of packing a good punch, but also vulnerable to being aborted or destroyed.

Subs
Your options here are decent and reasonably priced.