From: Houston, TX
A scenario doesn't have to be too huge to run into the unit limit. Combat tends to sub-divide units. But that can't go past 2000 either. So you can't even get the OOB close to 2000 before you start getting a force that shatters easily due to lack of ablilty to sub-divide (sometimes that's useful, of course; but not usually). And you hit that with the formation unit limit, too. Also, units can be needed for other things besides combat forces - replacement disbandments, for example.
And there's a whole list of other things that need to be increased. Map Boundaries, Event Slots, Force Formation Limits, Formation Unit Limits, Unit Equipment Item Limits, Placename Limit, Bigger Briefing, More Restriction Zones, Equipment File Equipment Item Slots, More Event Variables, etc.
Of course, there may be a price in performance to pay for this. In the past, TOAW I through ACOW were split into "normal" and "huge" versions to try to accomodate this problem. So, Arracourt didn't have to carry around the overhead of FITE, etc. I don't think Ralph wants to have to support two versions (that's why the "normal" version was history in TOAW III). We would be creating a "super huge" version, and we don't know how that will impact normal sized scenarios. But Ralph is just superb. He may figure out how to do it dynamically, or such.