So, once the visa application is done and the Thai Pass applied for, all that remains before travelling is to get a PCR test done (and copies of all documents!).
Am I missing anything else that needs doing before travel?
(Remember insurance, etc, has all been done for the visa application).
TLDR : Answer Summary
After completing your visa application and applying for the Thai Pass, the remaining steps include obtaining a PCR test and preparing all necessary documents. Ensure you have travel insurance as it is a part of your visa application process. Additionally, check flight availability from your country to Thailand, as some routes may still be limited.