Redesign and upgrade the website to redirect the focus from marine and other projects to architectural work as the main product with the goal of increasing sales both online and offline using a combination of SEO and real life marketing promotions.
Upgrade the software to a modern, dynamic, accessible CMS providing intentional layouts and views on all devices and orientations, with additional services to assist visitors with the quote or contact process.
Software - JOOMLA (not wordpress) chat / ticket system for immediate help, contact form with direct submission (connect with major CRMs like salesforce etc), contact booking software, hcaptcha (for security), video gallery connection to vimeo or youtube as this product lends itself to that level of promotion, more corporate than social media, municipalities, events producers, convention centers etc, high end clients who are not hanging out on tiktok or facebook. Also webmaster tools to monitor traffic and routes in with google analytics. All the software is self hosted, without monthly fees.
My suggestion would be to develop the new site on the current server in a subdirectory to minimize any downtime.