To answer several of your points, what I ma trying to accomplish is for the Starfleet to go looking for a technological edge and look for it amongst the many and varied ideas postulated by science fiction. The whole point is for them to try and recreate such things as Battlestars and Space-Fold technology, or planetary shields, impeller wedges or any of dozens of imaginary technological wonders humans have thought up in the past, but doing it within the limitations of Federation technology. Which is not to say any such research could not revolutionize 23rd/24th century technological theory; could, not will. Again, it's more a case of "this is a really cool idea, let's see if we can make something similar" than a "we should have one of these; prest-o, change-o, tadaa! there you have it" situation. They will run into walls their current tech level just won't let them barrel through.
They may also conclude (correctly) that some of what they have is better
than what fiction contains. For example, if the 'Enterprise' shape of a big saucer hull and two engine nacelles is genuinely an efficient shape for building ships, the Feds might not be doing themselves any favors if they decide to make their ships look like the missile-launching... things
of the Honor Harrington setting.
Uhm, wasn't there a long discussion on how fighters make no sense given how ST warp drives and phasers work only a few years ago?
Seriously, there are reasons that fighters and bombers were such an effective naval weapon in IRL surface combat, but they mostly had to do with airplanes being *in the air* as opposed to in the sea with the ships they are attacking or defending.
Manned space fighters are an idiotic brainbug, with a few exceptions for when you have special circumstances that give them some sort of advantages over a larger, more efficient hull.
ST does not have those special circumstances. ME and Starfire really don't either, though we can tolerate the excuses they make, because they sort of make sense on paper at least. It's only series like Ringo's Marching-verse or Card's Enderverse that have a real excuse for "space fighters."
Manned space fighters make most sense as:
-A reusable missile bus firing ordnance, if ships are designed such that fuel and reaction mass only take up a small percentage of a craft's mass, so that being able to bring back the 'bus' counts for more than the terminal velocity of the bus.
-A mobile defense platform against same (to expand your point defense envelope; effective range against an agile maneuvering target in space is not really that long, so being able to preposition a defensive weapon half way between the launcher and the target can really simplify your defense problem.
-A mobile sensor platform, one which can be left behind to watch things, or ordered to move away from the 'carrier' to get parallax on a distant object, or sent to get a close look at a big dangerous target.
All these roles are arguably better left to automation in 'hard' SF, where we take for granted that in the future computers will be much smarter and better than human beings that take up the same amount of space. Of course, once you take that argument to its logical conclusion you start to run short of reasons for your characters to do anything
dangerous, strenuous, or complicated. So a lot of series deliberately ignore that.
Note that "dogfighting" and "multirole" are simply not in the cards here; also that none of the roles I just described inherently work better with one or two man crews in your parasite craft than they do with ten or twenty in a much larger parasite.