good list. i'd add picking one number that means success before you start - enquiries, sales, signups, whatever. otherwise six months in you've got traffic charts going up and nobody can say whether it worked. and look at two or three competitors who rank where you want to be, their site structure tells you a lot about what google expects for your topic.
Yes, and it's less fancy than most guides make it sound. Roughly in this order:
1. Look at what you already have. Search Console shows which pages get impressions and for what. Pages sitting on page 2 are your quickest wins.
2. Keyword research, but group the terms by intent - someone searching "best X" wants a comparison, "how to X" wants a guide. One main topic per page.
3. Fix the technical basics so pages can actually be crawled and indexed. Don't get lost here though.
4. Content plan: improve the pages that nearly rank first, then fill the gaps.
5. Links and mentions, ideally earned from stuff worth linking to.
6. Check results monthly, not daily.
The mistake I see most is people starting at step 4 with no idea what they're already ranking for.
