Site Build: Replicating old site as new Wordpress site (multiple user-experience), mobile friendly, speed optimized.

I'm looking for a talented freelancer to bring an existing website up to date with a new Wordpress site. The existing site should be replicated in concept, with expanded functionality, and mobile friendliness, while also optimizing loading speed and responsive layout for best Core Web Vitals and Page Experience. After consultation, I'll purchase a hosting solution that meets our needs. Old site is [login to view URL] for you to review and understand how the concept basically operates for users. It involves multiple registration forms, two separate user experiences (writers selling projects, and executives scouting project), each with their own unique member areas where they view data, make actions, actions recorded, etc. As well, there is the administrative side that sends custom automated system emails with unique data embedded in message (example: welcome email, activity email, update reminders, etc.). The site also needs to be user-friendly for admin to create original articles to self-publish, as well as SEO optimization (maybe Yoast, or similar). Their will need to be a payment/membership management system using paypal integrated so purchases automatically update the term or status of member items. The site design will be created based on pre-created logos/images for the homepage, as well as for sub-pages. User-areas will need to be designed as well. I prefer that we work in phases per milestone released. 1/3 for design, 1/3 for tested functionality, 1/3 on final delivery. I'm a good employer with quick response/notes, and pay bonuses for good communication and delivery at end. I require a dedicated team within same company for consistent progress (no one-person that hands off to new sub-contractors). It would need to be tested inside of 3 weeks, and final testing in 1 month. I'm interested in hearing your opinion on coding language that may be ideal. Codeignitor? What is the most secure and fluid to use within Wordpress framework. Also, what you feel the best database type would be. Please don't do automated bids. I hope prospects read the requirements, and then I'll be very pleased to have a conversation to get work going.