The primary developer of Blenders Sequence editor Peter Schlaile has requested feedback and suggestions for improvement of Blenders Sequencer (referred to as a NLE - non linear editor in most other software).
The wiki page for suggesting features and giving feedback is here
The page lists both near term planned improvements, a list of already suggested improvements and changes, and gives space for further suggestions.
If you don't have edit permissions on the wiki, register an account here
Then email your user name to LetterRip AT gmail DOT com for edit permissions.
You will then receive an email back confirming you have edit permissions and then you can add your suggestions.