Well if there is any real opportunity to wear Germany down by landing in Northwestern then yeah jump on it…but me I’ve got so many figs and armor and artillery (not to mention inf) adjacent to there that I can drub any force landing there…the only thing good for the Allies is I need to take NW Europe for the NO so the Allies can counter right back.
But really the safer strategy is go heavy on Baltic/Poland with all 3 allies…but as you remark if Germany has the France factory they may have too many infs by the time the Allies finally take Eastern Europe…by that time Japan is knocking on the door and none of the Allies can take on the massive inf stack.
The only way to stop this IMO is deny Germany and Italy their NOs so they don’t have the cash to build up the raw numbers and have trouble defending France, much less retaking Leningrad or Stalingrad.
The France factory is a nice strategy but it’s not invincible IMO–it’s vulnerable to SBRs and if you can keep Axis cash poor by winning the battles for Africa and Leningrad early then it can backfire for Axis.