I’ve thought about this myself. If you’re fighting some minor back-and-forth land battle, or sending some aircraft to sink a stray enemy ship, you don’t want to break out the miniatures for stuff like that. But if there’s an epic land or sea battle, then that’s exactly the time to break out the miniatures!
Maybe there could be a house rule about this. If each side in a battle has at least 100 TUV present, then miniatures are used. Otherwise, the battle is resolved without them. (TUV = total unit value. If I have 12 IPCs’ worth of infantry and 20 IPCs worth of tanks in a battle, my TUV present is 12 + 20 = 32.)
When miniatures are being used, I think that it makes sense to give three miniatures points for every one point of TUV. Also, that TUV shouldn’t be regarded as a lump sum, but should be divided into categories: escort ships, capital ships, carriers, subs, fighters, etc. I wouldn’t object if a few leftover points were used on out-of-category units. For example, let’s say I have 50 points to spend on capital ships; but the capital ship I intend to buy costs 48 points. That gives me two leftover points which can be transferred to something out of category. When building my force, I should be allowed to spend no more than 15 points out of category.
These are thoughts which occur to me off the top of my head. I’d be interested to hear more from those who have thought more deeply about this; or who have field tested it.