Minimized folder: change the color of the size gadget to green if the folder contains active tracks.
 
Minimized track: change the color of the size gadget to yellow if track contains active FXs.

Not a bad idea at all.

Also, I could be imagining it but wasn't there an update / patch that included nested folders?

Would be great to have. For e.g. put each String section in a folder, then all 5 String sections in 1 folder parent folder. That way with one click one could close all 5 sections instead of having to close 5.

Small thing but it's a huge time-saver in the long run!