Hi DD,
and welcome to everyone!
Nice ideas there, but this mean that we have to do 3 independent campaigns (1 small, 1 medium and 1 large), instead of one.
If you take account the amount of time to make 1 complete campaign or 3 part-time campaigns, it is almost the same. On the other hand, one of the strong elements of a campaign is the building and evolution of the core force in addition with the fact that a player becomes sentimentally attached with his core force.
So, in the evolution of the campaign the player will try to protect his experienced troops (1st platoon) and he will have a core army with different experience levels (he will command veterans and rookies).
On the other hand what you propose is better from historical accuracy and way more easily from script point of view.
Look, what I suggest...
We do both ways!
We start with the synthesis of complete campaign and then by using the theatre of operations (maps, info etc) we split the campaign to smaller parts.
There is also another possibility...
The platoon will start as a "platoon"... US military advisors or Special Operation team in the early years of the conflict... and then in the theatre of Operations No2 they will be attached to Company (serving in another theatre of Operations ToO).
Then all this formation in the next ToO will be transferred as an attachment to a battalion fighting in the new ToO.
This way we may still keep a certain degree of historical accuracy by taking into consideration the actual units that fought in certain major battles with only a minimal addition of an independent attachment of for example a platoon in a company, and a company in a battalion.
I think such small modifications won't heart the historical accuracy of a complete campaign (and the gameplay benefits are very important).
The player not only will have the opportunity to experience the progressive increase in the level of command (Platoon then Company then Battalion then Reinforced Battalion), but in addition he won't lose his interest from playing the campaign (this usually happens when a player is playing several battles with the same core force).
Anyway, I agree with you. It is very easy to make it both ways, 1 complete and 3 smaller part-time campaigns.