Comparator? Easy-peasy...remove the Black VCA and the A-132-3, and replace them with an Intelljel Quad VCA, which then leaves you 6 hp you didn't have. Then, my suggestion for that 6 hp space would then be SSF's Tool-Box. So as a result of that swap, you now have one more VCA and all of the VCAs would then be variable-response for either audio or CV/mod work as necessary, plus the Tool-Box then gives you a 2-in summing mixer, a rectifier for positive offsetting and/or waveshaping, a comparator, an analog OR (gives the maximum of two inputs...feed it two LFOs and watch the mod curve craziness!), another inverter, and an electronic A-B switch. And all that for only $27 more than the current two modules!
There are ALWAYS solutions. They just require lots of poking at things. ;-)