In the Pac I like what KillOFzee laid out. I would normally spend 2/3 Pac w/US building mostly war ships early on. US is the hammer, and Anz cleans up, and grabs land. If Anz is getting income in the 20’s (very possible), I maybe build a carrier at some point, but mostly I like to have them build tpts, subs, and dd’s to trade tt’s/islands, and smaller ships w/Jap, and kill Jap tpts w/US & Anz. The Japs rely heavily on mobility, once they start losing tpts (and they will), it is tough for them to keep their income up (too many choices, not enough tpts/units so they have to give up some tt’s to you). A strong Anz can really be a thorn in Japs side, they can’t afford to continue trading dd’s & tpts (losing their dd cover) with the US lurking in striking range and keep a the land battle going in Asia. Like KillOFzee said sometimes it’s better to give up tt, and counter attack to kill Jap ground units w/o air cover. They are normally starving for ground units (try to make a Jap meat grinder or dead zone)
With UK Pac I like to build mostly mobile land units from the first turn (your income will most likely plummet fast). You’ll find that it’s hard to move out of India w/slow moving units because Jap can threaten all the coastal tt’s or India, and you can’t get back fast enough to defend if/when you enter China. UK1 I will normally move most units + 1AA (maybe 2AA now that India gets a 3rd w/new set-up) to Burma, and block sz 37 w/dd so Jap can’t hit my Burma stack (or India if they moved south & built a naval base on Kwangsi). For what ever reason in our games the UK India fleet heads to the Middle East, and sometimes ends up in the Med, but the BB can head to the Australian coast UK1 to be the defensive back bone for the Aussie fleet too.
In the 2nd turn, if the Japs have a sizable stack of land units on Yunnan, and another good stack somewhere that the Chinese can kill I might go for it and attack w/both China & UK. It really is a judgment call, but if I can kill the bulk of the Jap land forces in Asia, maybe have China build art on the next turn (Burma Road), get my war time bonuses for both UK Pac & Anz (make sure you also get Dutch NG), it might be worth it delaying the US entering the war. You can make China a quagmire for Jap in the right situation, and grind their Asia movement to a halt.
W/US Europe I build some tpts to get units to Europe (active Brazil w/2 tpts & 1 ground unit once at war etc…). Make sure you build a carrier & dds US1 & 2, and hope the UK has some ships left to offer cover for your fleet maybe at Gibraltar to start. You have to make sure your fleet is strong enough to get to Europe and survive (the Luftwaffe and subs can be deadly), and Italy/Germany get a 1-2 punch (keep in mind subs can pass through the straights of Gib regardless of which side controls it). Italy can also take a tt (like Algeria) giving the Luftwaffe stationed in W Germany a landing place for an attack on your fleet off coast of Gib.
UK Euro depends on if the Germans are going for Moscow, or England. A good German player may hold back some income G1 just to keep you guessing. Try to get control of the Med, but I personally don’t like to do mutual fleet destruction UK1 (Italy will generally get greedy and leave its fleet compromised away from the safety of the Italian air base, or attack you and you get better def rolls, or can counter their weaken fleet with RAF). If Moscow is the axis target the UK should be in position to get some air to Moscow at some point, or some fast moving units in from India/Egypt. They also generally reinforce US landings w/ground (AA), and ftrs.