Raise Ground Level Deck with 2x4s?

I'm planning on building a 16x25 ground level deck off the back of the house where about half of the area already has a concrete slab for support and the other half is grass where I plan on using concrete deck blocks as support for my joists which will be 2x6's. I know the number one thing for a ground level deck to last is having the most ventilation possible so I wanted to raise my joist/sleepers about 2 inches above the the concrete slab to allow for water drainage and better airflow underneath the deck.

My question is can I use some cut up ground contact 2x4 blocks to set/attach the 2x6's on to get some elevation and air flow under there? Is this something that will last or is there a better solution? I thought about patio blocks but they're a bit bulky and take up a lot of surface area under the deck which is somewhat defeating the purpose of what I'm trying to accomplish not to mention having to fire even more concrete nails to attach the joists. Obviously a 4x4 would work but that just seems like too much time and energy for only two inches. Just looking for something quick and simple any suggestions are appreciated!