First, looks awesome and I'm *really* looking forward to this game. Question: If DDs have good ASW and CLs have good AA, anti-screen, and torpedoes for large ships, why not just spam a bunch of DDs and CLs? I hope the CLs would get chewed up badly by the heavy ships but the way it's worded it sounds like CLs are dangerous to all but subs.
DDs and CLs are screens; their job, traditionally, is to protect the big ships. They can pack quite a punch (CLs), but they usually don't have much in the way of armour.
It all depends upon how the Armour Vs Penetration will work.
Obviously, if your armour doesn't get penetrated, you shouldn't suffer much damage, if it does then you should suffer a lot.
The hard part is when you don't have
much armour.
DDs, generally don't have any real armour so take little damage from anything, but suffer more than if they had lots & hadn't been penetrated. In most accounts of DDs being sunk by gunfire, the damage that kills them would normally be termed a critical hit. The way to take out destroyers is, basically, to fill them full of holes & score multiple critical hits. It's the
number of hits rather than the size of the shells that count. So lots of small rapid-fire guns (5" DPs anyone?) are the way to go.
Light cruisers should take a similarly proportionately low amount of damage from big guns (as the shells pass through both sides, as with destroyers, to explode relatively harmlessly outside of the hull) and take little damage from the small guns carried by destroyers (because they carry
enough armour to be protected) but should suffer disproportionately high damage from medium sized guns like those carried by light & heavy cruisers.
If the correct rock-paper-scissors balance can be achieved...
CLs swat DDs
CAs swat CLs & pummel DDs
BCs swat CAs & CLs
BBs swat CAs & pummel BCs
DDs (& some CLs) are virtually immune to large calibre gunfire and can to terrible/fatal damage to any ship if it hits with torpedoes. But (unless they're Japanese) they only get one chance.
It should also be remembered that BBs carry secondary armament similar to a CL (most "modern" US BBs had about the equivalent of an Atlanta strapped to each side) & BCs carry secondary armament somewhere between a DD & a CL. One item on my wish-list was anti-destroyer or "secondary" armament stat's for ships. Convoy attack, Sea Attack & Destroyer Attack if you will.
The pocket battleships should score damage (through penetration) similar to BCs but suffer as a CA.
Heavily armoured light cruisers, like some of the big US jobs, should get obliterated by battleships just as CAs would.