Hi,
I would add woo-commerce plug-in to make shopping carts in the WP website. If you want to make custom shopping carts then it would be best.
Photo galleries would contain the pictures which would be updated by administrator of the website.
This functionality will be discussed in details.
Thirdly, to do organic SEO, there is already plug-in available called - "yoast".
Let me your views too. Looking forward to your response.
Regards
Mit