I am personally in the pro-new nation camp, but I can understand the criticism of the pro-subfaction camp about potential Commonwealth and Italy new trees, and there are two main ones :
-There is too much copy-paste guns and vehicles in high-tier because there are not enough unique guns made in mass-production by these countries, so searching for the exact same gun/vehicle in a different tree will be very annoying
-This will further divide the playerbase because it is already divided enough between 4 nations
To address these two big concerns, I came up with a few ideas. I will take the example of Italy, because this might be the most complex new nation to implement in case of its implementation.
First, in the case of copy-paste weapons and vehicles, I have the idea of cross-tree progression :
Basically, if a gun was used by Germany and Italy during WW2, for example the MG42, you would only have to research it once, because the progression for the research of this gun would be common to the two tree :
Let’s say you are researching the MG42 in the german tree, and another weapon in the italian tree, your progress in the research of the MG42 will be the same in both trees, because it will be the exact same gun for both nations, so if you unlock it for Germany, you will logically unlock it for Italy too.
But these nations would strictly have in their trees the weapons that were only used by them : for example, the german tree would not have access to some italian guns that they never used, like the Beretta 1918, the OVP, the Carcano snipers… Same for Italy, you would not have access to the FG42 for example. Because these nations never used these guns. But that doesn’t mean that you will have to research again the italian guns you unlocked in the german tree !
The italian guns that would be removed from the german tree would be transferred to the italian tree, and of course, given the fact that you already unlocked them in the german tree, you would not have to unlock them again in the italian tree.
It would be similar for the german guns used by Italy : for example, if you already have unlocked the MG42 and have some of these guns in your inventory, you would not have to research it again in the italian tree, but the guns in your inventory in the german tree would NOT be transferred to the italian tree.
This would only apply the the exact same guns however, because if the caliber of the gun is different, then these guns should be different too. For example, the americans used the Lewis in 30-06 Springfield caliber, but the british used it in .303 British caliber (even if the british also used the 30-06 version, but that is another story), but these guns would be considered DIFFERENT, you would not have access to the cross-tree progression because these are not the same gun.
You can also note that the transfer would also concern the soldiers : italian soldiers would obviously be transferred to the italian nation, so maybe you would want to use that « nation-change » mechanic the devs recently introduced before the update that would implement these nations, if you want to keep soldiers that are currently italian for Germany, or if you want to transfer german soldiers to Italy. You would just have to use the « nation-change » mechanic before the update implementing the new nations.
Second, is the problem of high rank equipment :
We all know that Italy would really struggle in high rank battles, because they never had jets or heavy tanks like the Tiger during WW2, so I have an idea here too :
Germany and Italy were allies, and sometimes they fought side by side, but everyone had their own equipment, so for high rank tanks in the Italian tree, I suggest that you could use the high rank german squads with the high-rank equipment. For high rank battles, you could choose in the menu in the italian tree to equip the german squads with high rank equipment like the german Tiger squad or the german Me-262 squad, because while the italians and the germans sometimes fought side by side (italian infantry alongside german Tiger tanks), the italians never used the Tiger tank themselves, for example. This idea would be some kind of cross-tree squads in a case-by-case basis.
Italian soldiers training alongside german soldiers and german Tiger tanks (seen training to use a MG42 in the first pic):
Third, is the problem of the division of the playerbase :
That is an argument often used against the perspective of new nations, and it is understandable. Indeed, designing new maps specifically for a new nation would be long and costly. While this would still be something the devs should definitely work on, there are still other solutions too.
We know that Italians and Germans fought in Tunisia and Stalingrad (the italians were more on the outskirts of the city, but we can twist the arm of history a little, it wouldn’t be the first time for the devs after all), the British and the Americans fought in Normandy, North Africa, and the Pacific.
My idea would be to use the already existing maps for battles between two factions if they were present in this theater of war. For example, battles between british and italians on Tunisia maps, british vs germans on Normandy maps, italians vs soviets on Stalingrad maps, etc, etc.
And in the rare case of not having enough players of one nation in the queue for battle, the game could still match you with other nations on these « common maps », so for example, if there are not enough players playing Italy waiting in the queue, the game could fill up the ranks of the team with players playing Germany, so you would have Italy and Germany, because there are not enough players for an italians-only team, against USA on Tunisia for example, because italians and germans both fought in Tunisia, just like the US and UK. So instead of having 1 nation vs 1 nation, it could be 2 nations vs 1 nation, or even 2 nations vs 2 nations, but just in the case of not having enough palyers of one nation waiting in the queue, and of course the number of players on both teams would be the same as usual, this would just be a backfill mechanic to avoid dividing the playerbase.
Finally, why would we want more nations you ask ? Well, there are many reasons : we could just want to play on maps where Italy fought (for example that would be a good way to have more chances to play on Tunisia or Stalingrad), and it would also avoid to see soldiers screaming in italian in Berlin, which is very awkward to say the least. We can also just enjoy italian weapons, have italian customization only, and also, a very important thing : the devs could bring back some legacy squads (but only the italian and british squads of course) to put them back in the game, but in the new nations this time !
I have thought about this concept for a few weeks now, and I think that this might be a good idea ro reconcile the players who want new nations, and the ones who just want to have subfactions, just as it is right now.
I really think that this might be a cool and concept overall, because then, we could also apply it to other nations as well, I can think of France, Finland, Hungary, Poland, or even the Netherlands !
I think that’s all for now, tell me what you think of this suggestion, and give a like if you appreciate this proposition, because likes give more visibility ! 
I can recommend you a cool subreddit too, it is called r/FascistItalyPhotos, you will find a lot of unique and interesting pics, this is where I found some of the pics of the italians training alongside the german Tigers. Go check it if you like italian WW2 stuff.
