It doesn't look boring for me. The clouds are always moving and resizing over time, as long as the the mission maker selects a forecast.
Also the original sky comes with real stars. At least one mission of the CWC campaign is suggestive of that - the player has to use the stars for navigation.
Kegetys and Llaumaxx already created sky replacements.
Kegetys looks a bit pictorial, while Llaumaxx looks more clear.
IIRC disadventages of the Llaumaxx sky pack are sudden changes for weather and dawn, and more visible but unrealistic stars.