BTMRR is my fave because you're eyes aren't constantly adjusting to going in and out of tunnels. It is faster as the day goes on because the wheel grease get hotter the more the trains are run. JC can be good, but how good that one is depends upon the skipper, day or night.
Storybookland at DL is much better at night due to the lighting.
I understand the appeal of dark rides at night since your eyes are more adjusted to low light, and you can see more detail. For that same reason, I completely fail to see a greater appeal of Space Mtn. at night. When I first rode SM at WDW, having already ridden the one at DL, I was shocked at how dark it ISN'T in WDW (maybe something has changed since 1993, I'll know in a few weeks). Going at night, with eyes in low light mode, means it will seem even less dark. I have prescription shades, but bring a clear pair of specs to put on for all indoor attractions except SM.
Cheers.