The supplier roster, finally a first-class record.
Supplier records done right -- tax / W9 status, lead times, minimum orders, SKU links, preferred and approved flags.
Vendors is the home for everything upstream -- the companies you buy peptide APIs, excipients, packaging, equipment, and contracted services from. It is the master record the (coming-soon) Purchase Orders module will hang off, but the value lands the day you turn it on: a clean roster with the fields that matter for a real supply chain, not a generic address book. Tax ID + W9 status surfaced on every record. Lead time, minimum order, default currency, payment terms. Preferred + approved flags so the rest of the platform can prefer the right source automatically. A full contact roster + remit-to and ship-from addresses. And a SKU links table that catalogs which vendor supplies which part at what cost -- ready to graduate to a real FK the moment the Inventory module lands.