1. AMP Will Replace Your Website
AMP is a web components format and library and will take a white list approach. AMP offers lots of custom tags with loads of advanced custom functionality and comes with specifications on what standard HTML tags are okay to use. Using this format ensures the site will stay on a fast path.
2. AMP will restrict Your Design Abilities
There are very few limitations on how you can start your site. The only limit you have is your imagination.
3. AMP is for “Light’ Experiences
If by “light’ you mean not hogging your CPU and battery then yes AMP is for “light” experiences. AMP is targeted aesthetic content. Aesthetic Content is getting more dynamic with AMP with animations, sidebars, light boxes, accordions, carousels and more.
4. AMP is Purely for Mobile
AMP is designed for all surfaces and devices. It is designed to help publishers shift resources from the weight of supporting multiple platforms and allow you the freedom to create new and engaging content which will be available for all users on every device. AMP has been built from the ground up keeping responsive design in mind.
5. AMP Won’t Work With My Current Website
After reading the first four point you can see there shouldn't be any reason why you couldn't use AMP with the website you have right now. AMP is just a web components library. The AMP home page uses AMP exclusively. AMP isn't for everyone. AMP comes with restrictions and if you can live with them then go for it. If not then stick to your guns.