The track_ars ("Use track and release relationships") option is disabled by default.
Enabling it yields much richer per-track metadata (performers, composers, lyricists, related works), but most users never discover it because it's buried in Options → Metadata.

The first-run setup wizard already lets new users choose file organization, cover art, and update settings.
Add a short "Additional Metadata" page offering this option as an opt-in, with a plain-language explanation of what it does and why it's off by default (more data downloaded → albums load a little slower and it adds load to the MusicBrainz servers), so users can make an informed choice without needing to understand internals.

Rationale / analysis: Server-side impact of enabling it was measured and is modest — no impact on the search cluster (it only affects lookups, not searches), negligible database impact (indexed, fully-cached relationship queries, 1–10 ms), and at worst-case full adoption ~+12% WS-tier bandwidth. So exposing it as an easy opt-in is low-risk.
Since more data are downloaded it slows down Picard a bit, but it is an acceptable trade-off to get more detailed metadata.

Currently ~9% of users (mainly Picard 2.13) have this option enabled (based on log analysis).

Acceptance: New wizard page with the opt-in defaulting to the current setting; choice persists to track_ars; changeable later under Options → Metadata.