Hi George
It looks like most of it has been covered here but I thought I would mention a fairly simple way to do this sort of site migration. Firstly I would assume the all title tags, meta descriptions and h1 tags will be the identical to the site transitions. Understandably the URL structure may change slightly.
The number one thing is to make sure that that redirect strategy for the entire site is done correctly. This may mean crawling the entire old site using Screaming Frog to then map out exactly what URL will be redirected to what in the new site. Then your developers can structure this into redirects on the site. Depending on how many pages there are this may need tweaking to make sure there are not too many rules created to redirect the site.
In terms of making sure that each page is setup correctly from an on page point of view, this would be a very large task to accomplish. I am just typing out loud now but you could do the following:
- In Google Analytics export the top 100 (or larger depending traffic coming into your site).
- Export the rankings data that these pages are bringing traffic for organically (this will be difficult now not provided is the majority of organic keyword data but you may have historic data in GA that could help with this).
- Using the highest converting keyword for each page, use a tool such as the Moz onpage grader to fully check the page for any on page issues and an overall grade. You can then run the Moz on page checker on the new dev site and see if the grade is the same. If it is not then make the recommended changes to meet the checklist.
This is by no means an automated system but at least it is running each page using the highest converting keyword on the traffic bringing in the most traffic. This is the best way I can see this happening, it still isn't fully accurate as it is only checking the highest converting keywords but with the page potentially bringing in traffic from so many keywords it is very difficult to automate this fully.
But really the best thing to make sure is:
- The redirect strategy is bulletproof to ensure all backlinks are redirected to the new site.
- The title, meta and content is copied across so it is blatant to Google that the redirect is in the correct place.
I hope this help.