The D-Day map is hands down one of my favorite maps, but we all know there are extreme issues with balancing the attack/defense dynamic, so I propose that the attacking team spawns beachside regardless of nationality.
I realize there are plenty of German mains who appreciate the easy victories that are essentially handed to them from the top of the D-Day map, but it is absolutely no fun defending from an uphill attack when all of your defensive features are facing the wrong direction.
Alternatively, the objectives could be shifted over to the other sides of the ridgelines on either side of the map. That would provide more cover/concealment for defending troops to move onto objective without being funneled into a valley.
My final suggestion for balancing the Allied defense of D-Day, failing the implementation of the other two, is to give the Allied ships a more proactive role in the battle. The Allied ships, as they are, mindlessly trade shots with unmanned guns that magically fire back without any operators, neither does any damage to the other, and that goes on for the whole match. My suggestion is to have the Allied ships slowly zero in on Axis armor that is within line of sight by “walking” shells onto the tanks. When there are no Axis tanks the Allied ships slowly bombard on/near the objective with HE shells.
By tweaking the rate of fire, the accuracy, and the explosive radius/armor penetrating capabilities of the “bot” controlled ship’s guns you can increase or decrease how effectively the ships actually “balance” the flow of the match. (I’m positive that more Allied troops are killed by the D-Day ships than Axis troops, and that’s a bit silly if you ask me.)