It's worth noting that there are more than one ways to pan a stereo track. One way seems to raise the gain in the favored channel and reduce it in the less favored channel and leaves the L/R image intact. One way seems to move the full stereo image further left or right. The third (that I know of) seems to separate the channels and allow them to be moved independently. As a corollary to that, stereo widening (and narrowing) is another option. With those choices, I tend to leave stereo tracks stereo. There is often a reason why they are stereo beyond simply how they were recorded/mixed. Some effects even on solo instruments are stereo themselves and it seems best to try to preserve that.

BIAB 2021 Audiophile. Windows 10 64bit. Songwriter, lyricist, composer(?) loving all styles. Some pre-BIAB music from Farfetched Tangmo Band's first CD. https://alonetone.com/tangmo/playlists/close-to-the-ground