Since you already like Shotcut, two small GNOME-style apps can cover the light jobs, so you only open Shotcut when you need a real timeline:

• Video Trimmer (GNOME Circle): open a clip, drag the start and end, save. Very quick for trimming a single clip.
• Footage (Flathub): a little libadwaita app for trimming, cropping, rotating and converting one video.

Neither does multi-clip timelines, titles or transitions, so they sit next to Shotcut rather than replace it.

On Pitivi itself: it still installs from Flathub, but the last stable release was 2023.03 and development is very slow, so I wouldn't build a routine around it.

And if Shotcut feels busy for quick edits, the presets under View > Layout (Player or Logging, for example) hide most of the panels and make it a lot calmer.