You also missed SG-1-style Stargates. Those are always fun.

Seems
>rather unlikely, to me, that (a) nobody's ever been to another galaxy
>and back, and (b) that the Experts, now that they know at the very
>least that Kei's not in THIS galaxy, aren't out there in full force
>scouting the nearest galaxies. Maybe they are, but the vibe coming
>across is that "it's too far away". According to (very hasty)
>googling, the nearest galaxies are the Magellanic clouds, followed by
>the Andromeda galaxy, at ~250000 ly and 2,000,000 ly respectively.
>The first is only ("only", hah!) about twice the diameter of the Milky
>Way, which has already been crossed multiple times in-story, as it
>were. (Unless I'm misconstruing something and the Outer Rim
>territories are not at the, um, outer rim of the Milky Way).
>
>Ok, so, hard facts have no place in a story - this is Space Opera,
>dammit! - and I agree, to a point. But it's hard to believe that they
>can't hop in the saddle and hit the road just because of a piddly
>thing like distance. Anyway...

This pre-supposes that the current methods of FTL don't have specific Engineering and Navigational difficulties that we aren't aware of, nevermind the limitations they have in the orgional sources. Metaspace/Hyperspace in the origional B5 is difficult to manuver without powerful sensor's and/or beacons set ahead of time, and Star Wars-style Hyperspace has difficutly navigating closed-in gravitationally intense areas of space, such as the deep core of the galaxy, without slow and careful survey. I'm not saying that these are the reasons in UF, but I'm throwing out some examples.

Secondly, there's also the logistics/supply-line element of such a venture, as any real attempt at rescue will likely fail unless they go loaded for everything and the kitchen sink, or they know exactly where she is and take the chance that whomever's captured her isn't going to move her after they set out.

Thirdly, it's entirely possible that travel to and from other galaxies doesn't have other difficulties, such as menacing and horrible entities awaiting out in the Deep Black that are hideously dangerous and not to be trifled with. Afterall, look at all the things they've got crawling out and amongst thier own galaxy, nevermind others.

Fourth, the easiest solution would be the find the source of navigation and propulsion that brought Kei to her current locale in the first place, and use -that- to tromp about over to Andromeda.

All sorts of fun stuff.