Question

 A Relative Volume Envelope in Automation, so we can + or - dB, but the faders don't move is good for to do small adjustments without going each point and enter a new value.

Answer 1

I don’t think this feature is really necessary. You can already do this by adjusting the gain up or down in your last plugin. You can always insert the Mixtool plugin and use this to offset automation. Finally, you can also assign a VCA fader to one or more channels and use that to make slight adjustments to previous automation data.  You could even automate the VCA fader. Cheers!

Answer 2

Really missing this feature.

If you want to increase or decrease the volume of a channel, have to edit all the envelop points.

Would be straight forward if there was a Trim/Read mode like in reaper. Faders stay at Trim position, unlaying automation changes as usual.

I am aware of the last plugin volume or VCA, but that's hard to reach in the console for each track manually.