I dunno. Even though I have a bachelor's in computer junk, I'm more of a writer and gamer than a hard scientist. I know enough science to write and game and that's about it.
A good way to start is check out GURPS Space, it
gives a lot of options for space travel types that
you can build from. For instance, in Traveller, you
can't communicate in FTL, but in Niven's Known
Space it is allowed. Niven's FTL can only have
navigators that have psionics (latent or full) &
so AI can't be used for space travel (no psionics
in AI in his universe). You can check out some
of Michio Kaku's shows on the Science Channel.
He covered how space battle would be in reality
(basically ships don't fly around like they do in
the sky, but can turn and move quickly by attitude
thrusters, but they have to be controlled so you
don't turn too fast & break your neck from
centrifugal force (at least I think it's centrifugal
force)).
But in general, everybody has a different view
of Traveller. It's more of a framework than a
canon. You build on top of it whatever you want
to add (states it a lot in the CT books). Kind
of like different people had different D&D
campaign worlds (like Greyhawk or Dark Sun).
But instead of one world, or realm, you have
a galaxy (or universe).
But I digress..