Why does everyone have such a hard time with 'rockets' in SFB or SFC? Terminology is one of the things that has always been screwed up in this subject. Missile weapons come in three main classes: unguided, self guided, and remotely guided. The inference has long been on televised and movie Trek that photons are mostly unguided. In 'The Undiscovered Country' they converted a photon to be self guided to take out General Chang's cloaked BOP. Remotely guided 'drones' have never been seen on screen AFAIK.
What are photons in TOS? They are WWII unguided torpedoes, the kind of torpedo that everyone would be familiar with in the '60s. SFB was created by a Naval crowd who were fully aware that unguided torpedoes where old news and ATG (Active Terminal Guidance - self guided) was state of the art. Wanting to stay with the spirit of the TV show they decided to stick with direct-fire photons and used the justification that a star ships advanced ECM suite could defeat any torpedo sized ATG system. But they still wanted to use something that represented modern technology and expected future technology so they introduced drones and the fly-by-wire sensor based control system.
All of these guidance technologies are probably feasible and compatible with the technology base associated with Trek. As for why the writers prefer to stay with unguided photons I do not know.
PS. Missiles, rockets, torpedoes - are all the same thing. The only differences are the medium (air, vacuum, water) they travel through and the propulsive technology. The SFB/SFC issue has alway been the guidance technology question.