Send Devices With Wet/dry Slider

So if we could have Send Device with slider:
0% = 100% dry out
50% = 50% dry, 50% wet out
100% = 100% wet out

This would simply be more handy to use,
cause now theres only option to keep, or mute source, nothing between.

Or simply to have 2 sliders. One for dry signal, and one for wet signal,
so you can set them seperately.