Musing out loud: space flight

Hey, space-friends!

I have a novel idea slowly, slowly percolating in my brain: I know who the main character* is but not her name. I know how the setting feels but not its details or mechanics. I know how some of the side-characters are related but not how they influence the story (because "Plot? What plot? We ain't got no 'plots' here, no sir!" is still my main story-failing).

I realized while writing A Star to Steer Her By that I want to write something sci-fi rather than fantasy because it's much, much easier for me to do believable character humor in a futuristic setting. That brings up the question of what level and kind of 'sci' goes into the 'fi'.

( Cut for exessively long brain-dump about FTL, sub-FTL, and Space!Magic travel )

Did I mention this will be soft-sci-fi, not focused on this stuff at all? It will, but I need to work out at least some framework or my brain will never hear the end of it.

*There will possibly be more than one PoV character because I'm enjoying writing that way, but it started with her.

**Longer, if NASA keeps getting its funding slashed!

***The other methods fly in the face of special relativity, too, but they come with built-in phlebotinum, usually involving travel in extra dimensions (warp drives and Vorkosiverse necklin rods both 'fold' space, iirc, though the latter requires a wormhole which is itself a folded-space tesseracty thing).

Space Travel -- amazing science page! With extra science!

I explained my space-travel dillema to my housemate madalchemist, and he sent me a link to Atomic Rocket, which is a whole bunch of stuff about STL, FTL, weapons, propulsion, and you named it, all aimed at Sci-Fi authors.

Granted, the page is dedicated to Heinlein and refers to him frequently, but since it's in the context of "appreciating a modicum of accuracy in the physical sciences" and not "Having the faintest clue how people and societies work", I'm willing to overlook the Heinlein-fanning.