I am not sure if you are not familiar with SiteContent, but we have a larger subset of tools for writing (in particular for the web) within SiteContent.

https://my.wealthyaffiliate.com/content

We have grammar checks, 100's of sentence structure checks, duplicate content checks, etc. You can manage and monitor your writing progress and you can leverage templates to improve writing efficiency.

You have access to over 1 million HD images as well with insight content.

Here is the full training on SiteContent (and walk-through). I suggest you check it out when you get a chance. SiteContent - The Complete Walkthrough

Thanks for sharing!