Unit types and sub types

Currently there are Air, land and sea unit types with their own set of rules. I think they should expand these types. My thoughts were Land (same rules), Sea (same rules), Air - Air Superiority (current Fighter types), Air - Bombers (current bomber types except add an ability to be Strategic bombers), Air - Attack (Air units that only attack ground units (not bombing run)), and helicopters (land units able to cross small streaches of water if they start and end on land, also roads and rail do not affect them). I think that would add veriety to the units. What do you think?

good idea and for the land you could have offensive soldiers, defensive soldiers, assassins that are invisible and can kill chosen units in a stack, mercenaries that are hired soldiers by the government, and special forces that are stealthy and have unique functions like can penetrate enemy lines from behind and have a special feature of anbush.

For sea you could have air defense ships that are made to combat aircrafts, sea to sea combat ships that fight with each other with weapons and of course the modern aircraft carriers that transport aircrafts.

Don't forget submarines and shore bombardment ships!