They were designed for SFB not SFC so I don't think regulating them will work. Otherwise you have to regulate escorts only being flown with Carriers, carriers having to be flown with escorts, bombardment and commando ships only used on assaults, command cruisers flown only at the head of squadrons, etc.
That depends upon what his goal is.
Throwing in one history-based flavor point doens't mean you have to use the others if htey don't fit your campaing. He wouldn't have to do any of that if he didn't want to, since they don't address what he seems to be after. It sounds like he wants to add something to make behind-the-lines base killing a little harder. The real question is, would this do that?
If this rule adjusts play in the manner he wants for his campaign, then cool! (And if it adds a little SFB flavor to the mix, that's just a bonus.)
As to whether or not it would work.......... I'm not sure it would. Early in the game the fast curisers are my favorite Gorn base killers anyway, since they are our only ship with S torps. Tearing down a full starbase in a BF is a long and tedious job, however, so it might slow us down a bit once the bigger ships come out as other activities might look more rewarding.
-S'Cipio