I am 6’3″ and insulating the floor in my Sprinter van is not an option for me. I also plan to travel in moderate climate so it should not be an issue. Van came with OEM floor and I am keeping it. It is a very good quality 1/4 (plus) plywood treated on both sides.
I am removing and filling in most of the factory anchor rings to create flat surface for my flooring. But first, extra support blocks in 3 channels that run in the middle. They are deeper than other ribs. Since my subfloor is only 1/4″ it is important to get good support underneath.
I cut bench of wooded blocks and used construction adhesive to attach it to the metal floor. Doing it this way was easier to get the perfect height match with other ribs.