Your title is the single highest-weight field for both search relevance and the policy team's first scan. The trick is satisfying both at once. Here's the structure we use for nine marketplaces.
Brand + Core Keyword + Key Attribute 1 + Key Attribute 2 + Use Case
Keep it under 200 characters. Put the most searched keyword in the first 80 characters — that's what Amazon weights most heavily.
US: front-load the primary keyword; avoid any certification word without proof.
UK: British spelling (colour, centre) improves local match.
DE: keep the English core keyword (Germans search in English too) but make the safety note genuine.
FR / ES / IT: a localized title outperforms a copied English one — don't just translate, adapt.
No #1, no Best, no Sale, no emoji, no ALL CAPS runs. Amazon reads these as either spam or policy violations.