I think the Heavy Cruiser Retrofit and the Fleet Heavy Cruiser Retrofit, need something that make them stand out from the mass.
They are too similar to the standart Assault Cruiser, especially the Fleet version is way to conventional IMO.
These ships have just boring BOFF layouts and have nothing that would make them attractive for anyone. They could need a bit more firepower in exchange of some survivability.
I think both ships should get a additional tactical console and two tactical BOFF stations instead of one Lt. and a Ensign Tactical. In exchange their Lt. Cmdr Engineering should be made into a Lt.