Military? Not really. Each hull size tends to get replaced with the next bigger size when it becomes available.

Notable exceptions are building hordes of 1 attack 1 defense tiny hulls to park under a military starbase array and non-military use. A tiny hull freighter gives you just as much income as a cargo hull. Tiny hulls with nothing but a constructor module is the cheapest possible way to build anything, unless speed is a huge issue. Occasionally a bare tiny hull transport is the fastest, most cost-effective means to use one freshly-conquered planet to take another planet nearby.

Absent an unfortunate war declaration, I rarely have ANY armed ships other than array fodder and huge hulls - I can usually research up that far before anyone declares war. Oh, and the occasional pop-gun armed fast transport, for blasting enemy transports and other unarmed targets.

If you have scads of credits, you can make the smaller ships useful by putting HP modules on.  You'll obviously want to focus more on building larger ships, but there's no reason why you can't upgrade the smaller ships to get more use out of them.

I often use small hulls to give my military rating a boost early on, trying to stay ahead of the AI. Then I'll often research some miniaturization techs and better weapons. If at that point I do have some spare bc's it happens that I upgrade these small hulls with better weapons as these upgrades happen immediately, as opposed to the slower process of building new medium hulls.

Especially if I'm rushing to have a spin control center, these upgraded small hulls come in handy