So let me recommend looking at Copilot Polypus, his pedals are sick and the wave shapes are fantastic. It also does CV in and has a sequencer (the supreme).
I just finished my 7 knob Tremulus Lune, modified to have a smooth and symmetry knob as well as a space knob, allowing you to tweak the shape of the wave. It's not ideal, but it's very unique.. you can get ramp up, down, square, triangle, and then everything in between. It's an analog trem so it thumps a little in super choppy Gristleizer square mode, but it's certainly far more lush than the Gristleizer.
There's a PCB Steve from Small Bear sells called the tremulous bear, and it has separate speed knobs for each half of the wave.. It's very unique as well. It has a bias knob similar to the Gristleizer , but it definitely does not have incredible gain like that..
I dunno, the twin stags gives me a boner too
Yes I know the graphics are bad