I propose an enhancement for nested tracks in Premiere Pro. Instead of opening a new sequence on double-click, nested tracks would open directly within the existing timeline as secondary tracks (e.g., V1.1, V1.2, etc.). This would allow you to add or modify these sub-tracks without leaving the main timeline, making the workflow more seamless.
This feature is already present in other software for managing complex effects, and integrating it into Premiere Pro would significantly improve project management.