Fix WordPress Speed Bottlenecks

My WordPress site has become painfully sluggish—pages take far too long to load, the server hesitates before responding, and navigation feels sticky. A caching plugin is already in place, yet the performance gains I expected never arrived. I have not run any core, theme, or plugin updates recently, so the slowdown is unlikely to stem from a bad update.

Here is what I need from you: identify the root causes of the slow page load times, server response delays, and navigation lag, then implement targeted optimisations that bring the site back to a snappy user experience.

Key deliverables
• Comprehensive audit pinpointing bottlenecks (hosting configuration, database queries, heavy scripts, unoptimised images, etc.).
• Implementation of fixes—this may include refining or replacing the current caching setup, enabling object/page caching where appropriate, minifying and deferring CSS/JS, compressing images, and cleaning up the database.
• Post-optimisation metrics showing clear improvement (e.g., load time under two seconds on GTmetrix or similar, noticeably faster first-byte response).
• Short hand-off report summarising the changes so future maintenance is straightforward.

Please work directly on a staging copy first to avoid downtime, then migrate the improvements to the live site once verified.