You added a column in Redshift, clicked Sync Design, and it reported success. The column still isn't in the dashboard. That's documented behaviour: one unresolved mismatch anywhere blocks new column information everywhere. Here's how to clear them and stop them coming back.
Your homepage loads instantly and your dashboard takes eight seconds. That is not a contradiction: wp-admin is the only part of your site that never gets cached. Here is where the time actually goes, in the order worth checking.
Learn how to debug WordPress like a professional. Discover how to fix common WordPress errors, optimize performance, improve security, troubleshoot plugins, themes, databases, and server issues with this complete step-by-step guide.