A good use for recce planes is to temporarily highlight CVs and these convoys on the map. We can use Catalinas and Condors for that. Also, search and destroy missions in support of landing actions ... 
This is exactly my idea why the Fw-200 Condor and the PBY would be a great edition to the game, although both could carry bombs/Depth charges, I would love to see them in a natural Torpedo loadout and hunt convoys/CV's.
Its also possible to have simple Surface Task forces, A Large cruiser and destroyer escort, or two cruisers and destroyers.
Now for these Surface Taskforces, their function would be offshore bombardment, I am pretty sure we can set these up to be "manned" as in
you can move these TF's around the map as needed, without a carrier however you would need to provide CAP for it.
I would not consider adding a battleship as the damage done would be to extensive and unfair to the balance, however a pair of cruisers offer 6x 8inch batteries to fire, which is considerable bombardment.
The reason I am thinking of a separate bombardment group is simply - if the CV goes down in a CV taskforce, it respawns in 15 minutes, however in a pair of cruiser task force you would be required to sink both cruisers, which adds a level of difficultly to the plan of action.
The best idea I have so far is having 2-4 destroyers escort the convoy, which allow people on 5 inch guns able to defend the convoy if needed, also
most transport ships did have a fore/aft 3-5inch gun, so it makes sense those would be allowed to use.
Only difference is you cannot control the convoy, but you can man the guns for defense.