Having direct video rate control of those two pots would be very powerful. Much like some of LZX’s offerings where there are not direct ‘cv inputs’, there are ways you can patch your inputs and outputs to more dynamically interact with VEIL’s core function, assuming CW positions on the knobs.
Put your 3 input sources through VCAs (Bridge, Cadet VI, X, Marble Index, TVFKG, TVVCA, etc.) before patching them into VEIL and modulate with LFOs. Modulating the contrast (gain/attenuation) of all three sources at once will mean that as your LFO opens the VCA, you’ll see more of each of the layers appear out of black (increasing gain towards white) while at the same time the brighter spots of the upper layers will begin to obscure those beneath them.
Mix your 3 input sources directly with one multed LFO (Passage, Color Chords, VBM, Cadet VII, CMix, Matrix Mixer, forthcoming Fox Daisy, etc.). This will let you modulate the brightness (bias or how close to 1V/white each pixel is) of all layers simultaneously. The effect of obscuring lower layers is increased while maintaining the ratio of brightness between each layer. Your upper layers may blow out to white more readily depending on how much you bias them.
Patch all three source inputs through a Gamma corrector, like an Arch (ideally through a video rate fader for log<>lin<>expo fades) or Shapechanger. This lets you adjust whether your mid greys are closer to black or white under voltage control. So if you have a dynamic portrait, gamma correcting it would move its midgrey points without forcing details closest to black or white to be clipped. This makes VEIL dynamically adjust how the layers obscure each other without losing detail as readily as the summed LFO option.
If you decide VEIL is totally your thing, using 6 of them fed by a multed RGB image with 3 video rate faders (Marble Index, BSO Crossfade, TVFKG, etc.) would let you set up two scenes of opacity (pots on each set of 3 VEILs set differently) and then fade between them with a LFO. SHUTTER would do it too but as a hard switching effect.
As more of a thought exercise, using 12 VEILs fed into 3x Brownshoesonly Scanners would let you scan across 4 different scenes of fixed opacity at video rate.