Here are your answers :)
1) Yes Canvas will do this
2) I would use dynamic sidebar (woosidebar manager) to do this
3) Yes this is standard woocommerce use of categories
4) You will need an additional woocommerce plugin for zooming. Take a look at http://wordpress.org/plugins/zwoom-woocommerce-product-image-zoom-extension-by-wisdmlabs/
5) Lightbox is supported by Canvas but not add to cart within lightbox. Let me know if you find a solution to this one
6) Can you point to any example sites of how you would like the related products slider to look/function.
Let me know if that all makes sense :)