Should be easy to play test this suggestion since Code does it.
Say I have two pane columns split something like 22%/78%. Suggestion is double-clicking the separator between them resets them 50%/50%.
With more columns, any separator sizes all columns evenly. 33.3%/33.3%/33.3%, 25%/25%/25%/25%, etc.
With horizontal separators, it sizes all the pane rows within that column evenly.
Less time / more gesture options to manage panes = more time to focus on what you’re writing instead of managing panes.
Replicate what VS Code does.