Actually 30 for cruisers/heavys 40 for grands and 50 for bbs might work alright.
I don't think so.
We changed the Daemon's rules from bad to good, but that doesn't change the fact that you don't know if your Daemon will work out good ahead of the battle.
Ship caps aside, for +40 I'd rather upgrade a grand to a battleship. +30 on a heavy is also almost a battleship in some cases. And +30 on a cruiser will get you a heavy instead.
If these point cost reflect the rules of a Daemon I'd rather change the rules to justify a lower cost.
Setting availiability to "Reserves" would prevent Daemon abuse, but will almost certainly kill Daemon grands and battleships. Still, it's a compromise I could live with.
As with ship classes... I don't understand the fuzz about the Slaughter. Daemonbomb isn't the only way to use those ships. A Daemon is a lone cruiser somewhere in space... and in my experience a lone cruiser too close to the enemy fleet is a wreck easily made. Two Daemon Slaughters may be even worth turning our fleet around for one turn to get them.
I'd pick range over firepower on this case. I even considered a Murder (with lance option) because it has almost full firepower at 45cm. Not many fleets have the ability to catch it that far behind.