I'm not a fan of the chronological approach myself. I accept that there is a wealth of neglected aircraft and conflicts that could be covered, but that they haven't been done up to now says a lot - it means they probably wouldn't be that popular beyond a small bunch of enthusiasts - and that means they wouldn't sell as well.
I think the official releases should aim to cover as many of the big theatres of action (Eastern Front, West 42-45, N. Africa, Pacific) as quickly as possible. The minor aircraft and theatres could then be filled in by some third party paid add-ons similar to those for MS Flightsim. If the SOW series takes off as I expect, other companies will start producing one-off extra aircraft and maps - I think we'll soon be awash in more aircraft than we know what to do with!
