Create unique content for the blog/social media to achieve links... Use websites like rawshorts.com (video animation website) and canva.com (infographics), both are free and require no downloads but will help you to create unique content that may be shared/gain links if helpful to your audience.

I don't think that total word count is TOO much of an issue for e-commerce, however, it is key to have enough detail as possible in the description. We have products that we can't really go too much into detail as there isn't much to say, we can only write enough to ensure the pages are unique and descriptive enough to explain to the customer exactly what the product is, but often the word count is between 100-150. A key part of ranking for e-commerce is ensuring headers, page length, meta descriptions etc all up to par and make sure the page is as user-friendly and easy to navigate as possible.

We like to refer to this as a checklist when checking our product pages are as good as they can be. 
https://magento.com/blog/best-practices/seo-best-practices-ecommerce-product-pages