There's no reason that all the work done so far can't be leveraged into a series of add-ons. A destroyer command add-on is just one possibility. Everyone is clamoring about an Atlantik version, you KNOW in a year the timing would be perfect.
One thing is sure: in the simulation market (which is bafflingly small considering that is what computers were for in their infancy. Even spreadsheets were sold based on their ability to simulate), it is much easier to sell additional products to your existing customers than to develop new customers. Also, existing customers will be more willing to support a franchise they care about by paying full price to support the company which produces it.
As far as differing interfaces go, I'm a keyboard guy and SH3 and SH4 are nearly identical in that regard. Insert/delete to raise and lower the observation scope and pgup/pgdown to raise and lower the attack scope. And the devs made the entire keyboard programmable, so how can ANYONE complain about the interface????? Frankly, there's astounding quality here and much of the time we're (including myself here) blind to it.
Guess I'll have to abandon my Holy Grail of imperial measurements :rotfl: and play metric with the add-on. I hope it's metric only while you're on a U-Boat. It should be imperial only on an American submarine! Force the metric slaves to learn the superior system and they will learn to love it.
But only in SH4 Pacific, please.