Cantilever the joist out past the frame across a sill sitting on the piers. They should be sized to the load and length of the cantilever. The post mortice into the sill on the piers. Drop the walking deck below this level to allow water and snow to not effect the wall system. I would say it is not OK to keep it at the same level.

Why no extra roof? Don't forget your gutters. Might as well collect it for the gray water system.

Tim