Hi. You have control over how often you publish, comments, quality content, etc. However, you can't control the site health aspect, because it is calculated by how long your website has been up. As time goes by, you will see that percentage go up. I believe it increases a little each month. So, the longer it matures, the more Google will find trust in it.

From my understanding this is something that comes with time and increasing volume of content and visitors. Its one of those unfortunate things that you cant do a lot about.

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WordPress is old and klugy. Many modern tools are better. However WordPress have thousands of old users who I don't think are capable of learning anything else so it will be around for ever for small time websites. Marion has a way but I don't think the technical expertise is here for anything other than WordPress.

I found that wix is easier to customise a themes with more option. So I was wondering if I create the website from wix and link it to my WA account, so I can monitor my progress.

I believe WA works only with Wordpress...is there a specific reason you'd want WIX? Wordpress are the leadr in terms of content management and themes etc