The scylla, or cruisers in general, are ships that larger ships mostly see with their asses.
A battleship will always be behind a cruiser and the cruiser will shoot backwards.
The Scylla can fire all 3 heavies backwards and forward, that is good, BUT, while it has 9 normal turrets it can only fire 3 backwards.
Since Battleship shields are something tough, you pretty much need pulses, and since pulses should also be able to fire like heavies, you need to give them the 2 only slots of normal turrets that can fire forward AND backwards, leaving the Scylla literally ONE turret to fire backwards, WTF?!
As a battleship, if you want a cruiser down fastly, you cruise to it, recharge and unleash your fire, what would a Scylla do in such a situation?? You at least would have to cause as much damage as you can but then you can only add 1 more firing turret to your heavies, which means: A Scylla is easy as hell if you cruise up to it.
In case you want the Scylla to be a "all in moving forward destroyer" it isn't, especially not by reducing its powercore AND hull.
Against snubs:
Ever seen a Bomber kissing a cruiser from the front? -NO
In the case of a Scylla, a bomber would stay behind, making it possible to kick a Scylla's ass like HELL, what is it going to defend it?
Razors? NOPE, they will be gone.
Heavies? NOPE, have fun hitting a snub with cerbs and mortars
And of course, normals? NOPE, only 1 available.
BUT there is an easy fix for that.Slot 5,6,7 and 8 could easily get a more wide angle and done, additionally, make the removed heavy slot a normal one and you have one more.