Yes that was done before. Issue is the DD has alot of special abilities that cant be solved with battle sims. Of course, if he could not stop subs, negate the first strike of subs and just rolled at 2 at SB, we could compare BB, CA, and DD.
If the DD was reduced in cost, the fight of 8 subs attacking against 7 DD gives the subs advantage, reverse gives the DD advantage. So again we are not about to make the DD 7 IPC, or nobody buys subs anymore.
I think the cruiser problem is possibly solved by making it a 4-3-2-12 ( one hit unit), or alternatively, if the Cruiser is fighting any smaller ship, it attacks at +1 ( only against DD, CV, SS)