Not really something you can answer that simple. Fully vocally complete unreleased tracks or tracks with a workable vocal take should be released on new studio albums. Songs like Who Do You Know or What A Lovely Way To Go are in my opinion worthy of a release on album/single. Tracks that are not vocally complete but could work amazingly as a feature with another artist fall under that category as well. The songs that don't have a good enough vocal take to work with or a far too incomplete to work on, should then be released on anniversary releases or box-sets. The original versions in their "final" mix, should be released alongside the remixed songs as well of course.
But the rollout and scheduling of a campaign should be properly planned as well, meaning that you shouldn't just release an album and that's it, but make use of the momentum. The earliest best moment for that is of course right now with the biopic to be released in 1.5 months. After that, work with the 50th anniversary dates as a campaign era:
In early 2029, announce a limited theatrical release of the Destiny Tour in cinemas and soon after the Off The Wall 50th anniversary campaign and tease (not announce) future releases. Over the months, start smaller scale actions on social media, TV etc to get the Off The Wall era vibe back into the media. Release the 50th box-set in Aug 2029, consisting of the remastered album, demos of the album's songs and a selection of unreleased tracks which are not able to be included elsewhere, 7"/12" edits and instrumentals, as well as a compilation of TV/live performances of tracks (as seen in Queen I/II or The Beatles' Super Deluxe) at $169,99. Alongside, release the album on Blu-ray for collectors and audiophiles (24/192, 24/96, 24/48 1979 Original Stereo Mix, as well as the 2026 Dolby Atmos Remix) at $22,99.
Then in 2030, matching the Off The Wall-era, release a new studio album of a selection of songs done in 1975-1979, incl songs like A Baby Smiles, You Ain't Gonna Change Nothin', Susie, Goin' To Rio and several others which are vocally complete or workable, with several being released as singles. Soon after that campaign ended, announce and release the Triumph Tour concert on Blu-ray (as a theatrical release wouldn't make sense due to the concerts being on standard definition tape).
Continue with a similar structure for future anniversaries and you're fine till 2053.