uk strategies
Hi dojoboy.
I had some nice games with the uk, so I might have a few useful tips. Most decisions depend on the way you want to play, you might go for a land, air or seabattle route.
As UK you have an abundance of resources, so you will want to increase your IC whatever route you choose. I think improving all your provinces to 4 (maybe 5) IC will be best. You will need a lot of manpower for this, initially you may get rid of some ships to get it. Have a look at all your fleets, there will be some 'colonial sloops' which are quite useless for the battles to come, getting rid of the old subs will also be a good decision, then there are old destroyers which you won't need before '39. You will reduce your supply-need, get manpower and have the opportunity to research improved destroyer-models which can be built quite cheap and fast in '39. The construction of the IC will reduce your inital research-budget. You should go for the theoretical projects first and fill out the applications later (watch out for applications that will be needed for other applications, chosing the right timing here is very important).
In any case you will want to research fighter technology, I would advise cag to, they are very useful (and cheap) allround planes (but avoid airbattles against fighters).
You have about 20 divisions in the beginning, when playing a sp-game you should not leave them idle. There are enough transports around and you have the option to lend your troops to other nations. First you won't have to pay for them, second the other nations will bring your troops to full strength (saving your manpower), third your officers can gain a lot of experience and fourth you can help to shape the world to your needs. There are three wars to exploit, first ethiopia, not much hope to arrive in time and drive the italians back, so you might choose to stay out of this adventure (also ethiopia is missing the manpower that is needed to restrenghten your divisions). Helping rep. spain is a must, I think. It will be useful to choose a good commander for every division (no old guards though), command them yourself, the ai won't do too good. The third opportunity is the sino-japanese war, this might start between '37 and '39 (sometimes not at all), the earlier the better. You should try to destroy as many japanese divisions as possible and then drive them off the mainland (also from corea!). This will cost the japanese some years, easing your future in the indic and pacific. Your officers will gain a lot of experience, Monty ended as a lvl 6 fm in '39 in my game, good officers are invaluable and will give the germans and italians a very hard time. You will also avoid long idle phases, playing the uk this way gave me one of the nicest gaming experiences with hoi. Make sure to bring your divisions back to europe and africa on time (depends on the locations of your divs, around april should be a good time though). If you want to play further ahistorical move all divs back to europe, there will be no fighting in asia for a long time. Of course the historical uk could never do such large scale interventions, as you see my playing style was very ahistorical (but fun and effective).
This answer is already quite long, so I will give just a few short tips for the different routes.
Seabattle: research modern destroyers and improved shipbuilding, the diesel engines (or related) will give you the opportunity to improve your existing ships defense rating, this will be quite cheap and fast (so build no new ships but destroyers, upgrade the rest). Get good cags and some carriers. The royal navy will definitaley rule the seas then (crush the europeans axis first, then move your fleets to asia). You should build modern destroyers, they are quite powerful, while cheap. Once the german and italian navies are beaten you need destroyers only to guard your convoy seazones. To some degree you will have to follow this route anyway beeing a colonial, non-mainland power...
Airbattle: This would be the heavy use of strategic bombing. I never tried this, since it needs so much micromanaging.
Landbattle: You will have to improve infantry tech, tanks and tactical bombers for this route. A useful tool are tankettes with engineer brigades. They are (initially) very weak, but incredible fast. Use other troops and tacs first to break the enemy then chase the unorganized enemies with your tankettes (which will be faster than the retreating enemies). This works very well in africa where you won't have to fight enemy airwings. Later tankettes with engs have a defenserating like the powerful tanks, they can be used for guard duty and flanking, they are nearly as powerful as a inf division while beeing cheaper and using less manpower (I really started to like them playing the japanese where they would guard the main isles, in a few hours you can gather enough of them from other beaches to repel any enemy).
In france and belgium you might try to stop the german invasion right in the beginning, you will need a lot of fighters then, usually the enemy will attack only after they weakened your divs with their stukas and tacs - win the airbattle there and you might stop them. The major weakness of germany are its allies. Attack through bulgaria/romania or italy, force germany to guard a lot of fronts, there will always be opportunities to attack. As long as you guard the channel with planes and ships they are forced to the defense, you decide where and when the fighting will be. If you don't beat the european axis before the japanese join you will face some hard fighting on a lot of fronts, you will need the americans and russians then to do the major fights. So better avoid this (or better not, might be exciting).
You could also try to isolate germany using diplomatics, I suppose the game will be less interesting then...
Hope this helps, nice gaming...
h