I'll be adding this to our Data & Trends section later.
There are many, many ways in which plastic waste could be better identified, collected, sorted and recycled.
Changes in culture and environmental concerns (which we're already seeing today), widespread use of reverse vending machines (i.e. cash incentives for the public), advances in filtering/sorting machines, robotics and drone patrols/collections, satellite views, etc. Also the use of home and office machines to break down stuff easily and reassemble it.
Any other suggestions, please post them here.