@Northerner I believe that the cluster missile price is too high. It doesn't do significant damage, while the increased cost of both factory and launcher makes it more difficult to use.
I was working on this (unfinished), and I noticed it really struggles with ships in its tier. The initial volley is huge, but almost useless against a properly designed ship.

I suggest upping the damage, adding more cluster missiles spawned from each initial missile, or lowering the cost of the launcher and/or the factory.