Faith, I completely forgot about those! And the college-themed lamps, too - all late 90s stuff.
The Midnight was really the lamp that brought popularity back. Not only was black THE 80s color for electronics, but whereas formerly, the Lava Lite was designed to blend in with fine decor, the Midnight would disappear in darkness, leaving only the glow-and-flow standing out. In my opinion, DARK room = Midnight, preferably white/blue. Dimly-lit room = Aristocrat, also white/blue, with its sparkly base.
The Starships were nice lamps. The swirls are nifty and showed hand-made care; I still want one of the multicolors, bot the blue and purple swirls already. Silver Streaks are classy too, and fit in well in any decor - I just picked up two in colors I didn't have before, blue/clear and yellow/clear.
I don't know, I think Lava could bump up their quality slightly and still meet production. Thing is, the modern consumer has no idea what "good flow" looks like, nor does he generally care; it lights up, it blobs a little bit, it's a lava lamp, end of story.