Keep in mind that this polishing effort is not the last time you touch the site, it's just what you need to launch an effective site that you are proud of.
Do your home page last. It might change as you tune individual pages and posts.
Do all other posts one at a time and in order of most simple to most complex.
Since a good portion of this work will be about images set aside time where you will feel distracted.
Finding and modifying images can be absorbing and fun, but is also a real challenge.
Wix has a lot of great images, but so does Google.
Spend the time you need here because good images are super important.
Once you have your text in good shape find someone to proof read it. It's just tooo easy to miss your own grammar mistakes.
Plan on spending around an hour per page. Some will go quicker, some longer.