Hello @setsunati, this is a feature request for Steam, not Proton itself, and is effectively a duplicate of https://github.com/ValveSoftware/steam-for-linux/issues/5687. Also possibly a duplicate of #1714.
Closing in favor of the existing issue reports.
Protontricks is a wrapper for Winetricks that makes it very easy to install game dependencies into the Proton prefix and configure.
https://github.com/Matoking/protontricks
Protontricks button in game Properties will be awesome so you can just click the button which will launch the Protontricks GUI (which opens Winetricks GUI pre-configured for Steam games) and you can easily install required game dependencies.
Visual representation: https://i.imgur.com/vCPnJl5.png
Clicking the Protontricks button will automatically grab Steam game ID and launch this command:
Example:
protontricks 377160 --gui
And then you simply install game dependencies and configure what you need straight in Winetricks GUI pre-configured for Steam games.