I'd go with the malted rye - Weyermann makes a great rye malt. I think you get more of the rye flavor and aroma from the malt vs flakes. About 5-7% will add a nice fruity aroma, a peppery, dry kind of finish. The mash is more gummy, and filtrations are harder, due to the higher beta-glucans. You might want to add rice hulls to the mash to compensate.