What should not be forgotten when changing CMS?

Question

Google

I'm going to change the CMS at IM. I know that from the beginning there will be a drawdown in positions, and then everything will recover. But this is subject to the fact that everything was done correctly) I threw in a list of what needs to be done:
- keep the same title
- keep the same description
- keep the same H1, H2, etc.
- save all texts
- set up 301 redirects for all pages whose url changes
- save all internal links (for example, from an article to a directory)
- keep the structure of the main page
- set up robots
- set up htaccess
When performing these items, such positions should be saved. Maybe I forgot something?

Answer 1

(add item) Save domain ownership confirmation identifiers (from search engines): HTML files, tags (if you did it through DNS, then you don’t need to) and don’t forget to check their availability.
It is better to use Screaming Frog SEO Spider BEFORE (saving the report) and AFTER.
Then don't miss anything.
PS: Yes, and check the spelling in all the texts on the site! ;)

Answer 2

sitemap save
saving old URLs, as I understand it, it is wired in paragraph
Or are you going to change them?

Answer 3

A complete list of what needs to be done:
- save micro -markup
- save internal content for pages with traffic (texts, pictures, tables, lists, etc.)
- save webmaster verification and statistics
- save goal scripts
- check the technical part with netpeak or screaming frog before and after transfer
- keep the same title
- keep the same description
- keep the same H1, H2, etc
- keep all texts
- set up 301 redirects for all pages that change urls
- keep all internal links (for example, from an article to a directory)
- keep the structure of the main page
- configure robots
- configure htaccess
- configure sitemap.xml
- configure last-modified and if-modofied-since