Better Amazon Echo volume control


I have several Echos at home and have some connected in groups.

I am currently still missing a way to change the volume comfortably.
I would be nice to have a map on which only volume controls for selected echos are displayed.
It would be great if I could create volume controls for my groups.
And Perfect would be if I could change the volume in a group in proportion. so if speaker 1 is at 10% and speaker 2 is at 20%, I could increase both by 10% to 20% and 30% at the same time with one slider.
Is there such a possibility?

It appears as no one ever offered you suggestions. I used to have volume sliders on my lovelace dashboard, but some time late last year they disappeared. Have you or anyone else using alexa media figured a method of controlling volume in HA? There are actually TWO volume controls I would like to interface again with HA; Speaker Volume & Alarm Volume. Any guidance would be greatly appreciated!