This is an opinion/strategy question which is hard to answer. Generally though, even if you make an author page on a website, search engine placement for your Amazon page is going to be higher than your personal website.
That said, it's still good to have a presence outside the Amazon universe. Amazon is cluttered with promos to other products. Book marketing guru David Gaughran wrote, “As I write these words, there are currently 248 different titles on the product page of the Kindle edition of “Let’s Get Digital.” Between the ads, Also Boughts, Also Vieweds, Amazon promotion, and other links, there are hundreds of things that could distract a reader before they purchase."
You have a lot more freedom to put multimedia, bios, blogposts on your personal page -- and obviously links to other bookstores. besides, The amazon author page doesn't really generate many leads. Even though it's owned by Amazon I would still establish a web presence on goodreads.