@Cornwallis I play mostly OOB with Bid now. The general gameplay involves Germany slowly advancing on Moscow and capturing it around G10-G14 while making it costly for the Allies to have a strong foothold in Western Europe. Meanwhile China gets enough support in the bid to prevent the fall of India for quite a while.
The United States spends the first turn of income in the Pacific but then shifts towards Germany to allow an eventual invasion of W Europe or Scandinavia.
You should look through more League matches of top players like Andrew or Farmboy to get battle-tested strategies that can win even with +50 bids for the Allies. Small details make a huge difference when you are facing a master who can battlecalc all scenarios and find minor tactical flaws. One extra fighter can make a huge difference in the expected outcome of a battle.