This is a fixed bid, Allies get 1 additional factory to place anywhere they like.
Optimal locations would seem to be Eastern Canada, South Africa, Brazil, Alaska, Egypt
The idea here is that pre-placement bids can be overly distorting. Anything above 6 ipcs and you can get inf, artillery, tanks and subs. Anything above 10 and you can place a fighter. 12 and above gets you a bomber. Any of which can swing an early battle to break the boxed set up. 15 gets you a starting factory. But who would ever do it? When you could have a bomber and an inf? or 4 infantry, or 2 tanks, or 2 subs, any of which would give you a better shot on breaking a key early battle with overwhelming odds. A fixed starting factory bid on the other hand, seems less game breaking for early battles, it doesn’t jack up the balance for the unit set up, and it puts another target territory on the board for both sides to ponder and fight over. To me this seems to recommend it over a bid for ground/sea/air units, which are always used to break a round one battle. By stating before hand that Allies get 1 additional factory fixed, but they can place it anywhere, you give interesting production options and variety to the game, without putting the whole game into the opening battles.
Consider the possibilities…
Eastern Canada: the safe zone, gives UK an Atlantic naval option and a facility from which to drop ships into sz 1 and sz 10. Its usefulness will probably be exhausted by the time of the end game, but early on it could help the Allies to get something started with a quicker Atlantic crossing.
South Africa: the classic, a launching pad for tanks to help cover the African continent, support Suez and India. To resupply inf, or build ships, or air to cover the southern Hemisphere.
Brazil: the drop launch, gives USA another way to push ships across the Atlantic and provides a quick shuck into W. Africa. Its value at 3 provides USA their best production, and relative safety, but Brazil is also landlocked and somewhat out of position. Still it does help to cover the southern hemisphere and the transits into sz 13 or 23.
Alaska: cover north, gives USA an option on a northern movement for the Pacific fleet to pressure Japan from this direction and provide some assistance to the vulnerable Russian far east.
Egypt: the zombie, living or dead or undead again, as the factory could potentially switch hands! Provides an early and perhaps decisive Allied advantage in Africa and the med, but also draws the immediate attention of the Axis, since it is right on the doorstep.
Perhaps there are even strategies for a factory in other (less productive but strategically interesting) territories, like Archangel, Hawaii, Australia, Szechwan, or who knows? But it gives the Allied player something to work with, and the Axis player gets another target and doesn’t have to watch their start get broken in a round 1 bid battle.
I think any of these could make for an interesting alternative to the standard game, without putting the whole bid just into the first round of combat. As the Axis player, the main draw for this as an alternative bid is that you don’t have to face a distorted first round, and Allies still have to spend money to push units out of the new factory, wherever it ends up. Maybe the factory can be seized? Or if it goes in Canada, or Brazil at least you can still focus on the Eastern Front while the Allies are busy spending money on the other side of the ocean. If it goes in Africa, could be taken by Japan, or just serve as a distraction to the Allies while you focus on Russia. If it goes in Alaska, perhaps the Japanese will step up to the challenge and give Germany some breathing room, while USA spends money in the pac? Either way, it seems that Axis can still win the game, especially if they don’t have to face down a crushing first round bid battle.
*A factory in Western Russia? Could be interesting, but I suppose that breaks with convention, should clarify for simplicity, a factory ‘anywhere Allies control’ at the start of the game.