Uniqueness is a super cool feature for any kind of website. Won’t you stay back and spend a bit of time for something new and attractive than the usual view to your eyes?.. Same with the websites too.. That is why in website development area being unique in every aspect is so important. As it has some brighter side like attract more visitors which improves the business of the company, it has some non great points too (I wont say it as a bad point).
Until today most of the web users are humans, and after years of getting used to with the traditional website designs, most of the users expects a standardized structure for any website they are going to visit. It includes the following ;
(1) The top bar navigation menu and a search area
(2) Standard grid layout for Login/Signup and the sidebars
Some of the new generation web designs exceeds user expectations and showcasing a complete different pattern and structure to them. Say, some websites has a full page slider and a n arrow to go to the actual standard site or the one where the navigational menu is in the bottom of page and the rest of top area is filled with so many images and all. Its hard for humans eyes to quickly adjust to the completely different structure from which they are used to be. Hence it can reduce the visitors.
You can choose the uniqueness according to your expected visitors. If a fashion designer company put a complete new structure it will be an amazing site and people will still be interested in it. But say a government site with all new feature sliders and completly different structure, imagine a situation when people who are coming with some specific topic to search cannot even find a search button and it took them few minutes to figure it out how to get the search they will be quite disappointed.
So I would say as per visitors you can control the uniqueness, you never has to stop the uniqueness of your site as long as you know your audience.
Choose wisely,be unique and be successful. !