you’d want to watch out with phasers, distortions, and short delay times (like choruses/flangers or just delays) –
unless they have a blend control (like the Alesis FAZE phaser, the Bass Big Muff [distortion], or basically any chorus pedal) you can run into sound cancellation problems with deep bass.

Also you’d probably want to do digital rather than tape or analog delay – those both run though compander circuits before the delay which can lead to subtle EQ changes that would negatively affect the taurus’s sound.

Also, have you considered rack or table top effects? I mean your feet’ll be busy playing the Taurus…

The Alesis MODFX line is pretty much ideal, imo. The phaser, flanger, tremolo and compressor are just flat out awesome, the filter I’m sure you’d have a lot more use for than I did (you can sync it to an LFO and sync that to whatever) and if you really feel like shelling out for them, the bitcrusher and vocoder are pretty rad too. The first four you can find for about $40 on ebay; the filter is generally under $100 and the last two can go for up to $300. The modfx units also have serial ports on the side so you don’t need patch cables – just click them together like legos.

Also the Alesis ineko is a really nice tabletop unit (it also came in a rack version called the Akira). Very simple, just use the arrows to scroll to the effect you want on the matrix, each effect lists what the three knobs do under it.

A Korg Kaoss pad would be a good option too, probably the miniKP, KP2 or KP3 rather than the original – the original has some headroom issues.

If you’re not using the midi out on your taurus, you could hook up another synth and use a DJ mixer or Morley FXblender to crossfade between the two. I’d recommend the Korg EA-1 as it can be had for about $90 and you can use the audio in to process sounds with the oscillator options (ring, sync and cross mod) + the filter, distortion, chorus, etc.

As far as EHX options, I’d look at their array of envelope filters – the tube zipper, the Qtron/Qtron+, the Dr Q, the Bassballs, the Enigma, etc, as well as the Ring Thing, Stereo Memory Man w/ Hazarai, Bass Big Muff, Ravish, Talking Machine, and Black Finger.

Other more ‘pedal-y’ options would be the Moogerfoogers and the units from KOMA Elektronik (which does open up some interesting options with their light controlled expression pedal.)