Would this be considered enough content to add AdSense to my site if I made a niche blog with reviews of the products and affiliate links for purchases to the products via Amazon? Or would that get me banned.
if you already have an approved account, it shouldn't be a problem. make sure it looks like a normal blog and not a sales page. -just make sure your reviews are good quality, have sufficient information and are useful for the reader. -limit your affiliate links to 1-2 per post. -once in a while, make posts that aren't sales-oriented and without any links.
I think it should be enough if you are reviewing some number of products and the reviews are not copy-pasted from anywhere.
If you have a Google Adsense approved account, then it doesn't matter where you place your ads unless you follow the guidelines strictly.