ground level deck drainage suggestions?
I like what you've done keeping the framing above grade. However, are those poured piers or are they concrete blocks sitting on grade? Hard to tell in the pic. Since you're asking about drainage, ground water is apparently a concern in your area. If that is so you first want to make sure that you sink piers to give your deck proper stability. No matter how good your drainage system is any foundation sitting on grade will eventually be compromised by ground water.
Assuming your piers are stable building french drains under and around the deck to channel away ground water is a good approach. You shouldn't get a lot of precipitation passing through the deck. The main concern is to grade around the deck to channel water into the french drains and away from the deck. Likewise proper grading under the deck should prevent pooling and move it into the drains.