It depends on the purpose, really. What would the doctrine involve? Would it replace the fleet? Increase protection for medium size colonies? Why can't space stations do these things?
In a similar vein - In previous aurora versions you could get ridiculously fast ships around 400-600 tons or so. Classification as a FAC (which requires < 1000 tons) helps a lot. What kind of laser could we put on a ship like that?
I remember using that to create some company dropships, to board and capture vessels that have been disabled. Speed is key for that, as success chances depend on the speed difference of the vessels involved back then. Those may also be fun.