What I was trying to say in my initial post, is that I believe the salt additions, and particulary the high chloride to sulfate ratio, made the beer creamier. The stout without additions was astringent whereas the the first beer was maltier and creamier, with a much smoother roasted flavor. I mashed both recipes with the roasted grains by the way.
Also, you may consider increasing the lactose a touch and adding flaked unmalted barley.
As a side note, the mash conversion for the RO beer was fine and the beer finished with a lower FG than the adjusted beer, although I agree, it's not a best practice.