Hi Terry
Yes automatic columns and scale-able thumbnails would be ideal (e.g. small | medium | large, or use a slider bar).
A similar dialogue already exists with the QVLAYOUT command, which has a good interface, so I would suggest building on that.
QVLAYOUT lets you scroll horizontally across the full rolodex of layouts (not possible with the conventional tab viewer), and as a bonus it lets you loop back to the first layout. It spans multiple displays which is good for making the most of the available screen real estate, but if the viewer is restricted to a single display only that is OK too because of the ability to scroll horizontally (ideal when there are hundreds of tabs in the drawing).
Currently you can pin the viewer to the bottom tray so that it floats on top. And, like you suggest, it disappears once a layout is selected. Making the command available from a right-click on the layout tray would also be very helpful. Right now it's set up as "QV" in my keyboard shortcuts.
One suggestion to the developers would be to make it possible to select multiple layouts within the QVLAYOUT command. With the conventional tab setup, you can shift+left-click to select multiple layout tabs, and ctrl+left-click to toggle selection on/off for individual tabs. It would be a helpful addition if this was also possible for QVLAYOUT, because then you could then cycle through all the tabs and pinpoint exactly which ones you want to batch plot/publish.
Keen to hear your thoughts
Many thanks