Making a simple one-knob performable vibrato

I would like to make a control that controls at the same time the rate of LFO and the amplitude of pitch and those ranges should be customisable to tweak a nice musical vibrato that I can perform with a knob on my komplete kontrol mk1 keyboard.

This is something that is for instance achieved very easily in Massive with a macro control and adjustable ranges of modulation on vibrato rate and depth controls.

However, in FM8, mainly I think because there is no convenient way to map multiple parameters to one control (except the x/y morph pad, but unfortunately the controls I need are not assignable to morph pad ), also Komplete Kontrol software doesn't allow mapping more than one parameter per knob, so I ran out of ideas how to do it.

I am not an FM synthesis expert, I am just modifying useful presets to make them as playable and expressive so I guess if there is a way at all it would be with FM synthesis itself so I would really appreciate help on that.

For some patches the vibrato knob in Easy/Morph tab works kind of okayish, but still it is hard to play it right since it is bipolar.

Thanks, cheers!