That said, I began my search again for a method of making digital goopy sounds.
I managed to get a decent result with Sytrus + some pitch vibrato, chorus, and flanger effects mixed together. Here's the initial sytrus sound, followed by the result after filters. (I edit Sytrus while the filters are on.)
Before filter: https://clyp.it/b3mdkj0n
After filter: https://clyp.it/a2vzsbb4
One of the benefits of this method is that Sytrus nor the filters have their timing syched, which means that all the little worble noises that make up the sound will be slightly different each time. As a result, you can record a series of notes at different times, and pitches, and get variations easily. An hour or two will get you around 28 sounds.
This was already a decent result, however you can also change the pitch and speed of a sound, and then "compose" with it.
This is the same sound as above, but "arranged".
Basically, you can take one sound, or even multiple sounds, and compose them like you would a song. Especially by combining multiple sounds, you can come up with entirely different results.
This is actually pretty handy for all kinds of sound effects, by the way, and it's part of how I make sound effects. To give a quick example, here's FL Studio's default snare drum "composed" to sound like a gunshot or something.
Lastly, the other benefit of this method is that I can actually use it with the recorded sounds to make them sound a little more digital.
Original recorded sound: https://clyp.it/0kraw0hh
Same sound with changed pitch and arranged: https://clyp.it/njmna1us
Of course, now the only problem is that sort of have too many options. Too many is better than none, of course. That said, I do get suck of staring at waveforms for hours on end, though, so I'm looking forward to finally settling on a set of sounds and being done with the revision.