Hi there, this idea is inspired by the Gullfoss VST and maybe it would be easy to implement.
Inside Gullfoss you can adjust what frequencies will be affected by the plug-in. The same concept could be implemented in Vital, where you have a handle on the left to exclude low-frequencies to be affected by the filter or the effect. On the right you would have a handle to exclude high frequencies to be affected. I imagine that would be wild on comb filters, formants filters, flangers and delays, especially if you could put one of Vital’s LFOs onto them.
For further info on how the Gullfoss frequency limiter works: https://www.youtube.com/watch?v=ibeMz1U8yXE&t=138s