Sure, you have a point, but I am thinking of the most flexibility for everyone, including those who play out live on gigs. I didn't want to get too deeply into GUI design: not my area of expertise, and not my responsibility to speculate how difficult the changes would be. However, since you asked, what I envision is that the mixer can be toggled off. What I should have added is that it could be dragged.

I don't see this as requiring two actions to do one thing. Just toggle the mixer as follows:

When the new mixer is hidden, there would be one double-height row of toolbars at the top, with tabs to select which one you see. Then there would be a single height transport toolbar. The chordsheet would come up and abut just below the now-smaller area for toolbars. Two rows of toolbars of space saved.

When the new mixer is viewable, it could be dragged anywhere just like the old mixer, so you could position it anywhere over the chordsheet, which is still much larger than now because of the smaller toolbar space.

When playing live, perhaps you might not want to use the new mixer, and instead have up the small older mixer?

BIAB 2025 Win Audiophile. Software: Studio One 7 Pro, Swam horns, Acoustica-7, Notion 6, Song Master Pro, Win 11 Home. Hardware: Intel i9, 32 Gb; Roland Integra-7, Presonus 192 & Faderport 8, Royer 121, Adam Sub8 & Neumann 120 monitors.