Should bottom wall plates in a basement be treated lumber?
In my state the bottom plate is required to have the foam seal and treated lumber for external load bearing walls only. I do use foam internally but not treated lumber. The foam prevents moisture from wicking into the plate and rotting it. I do use the foam inside but more often  I will use tarpaper as I usually have a roll and it works well and is cheaper than sill seal foam. What you are doing will last but is a bit over the top (one of my buddies says I am over the top with the tar paper). In the case of a flood, the Sheetrock itself is going to wick the water faster than the wood will. I like the barrier under the plate be it foam or tarpaper.