Well, you already have the ability to edit the OOL, so that’s a wash, right?
Planes not hitting submarines isn’t too big a deal either, the person can just edit the results each round to account for it without too much effort. Guess you might want to separate the results of fighters and cruisers.
You’d have to add in a new naval unit, but I assume from my limited programming knowledge, you can do most of that with copy/paste.
tech could be a nightmare, but common, tech has ALWAYS been a nightmare! So ignore it. Many of them can be “fudged” anyway.
You already have Hbombs. There are no defending jets anymore, attacking jets can be put in like normal bombers. Transports don’t defend, so don’t even have a column for them (hey, make it the new navy ship!). Things like Imp Factories, Imp Shipyards, War Bonds don’t need programming.
Radar is possible, but that can be done by fudging too, just program in infantry vs bomber or whatever. (Make sure you have = number of infantry per attacking aircraft being AA’d).