LOL, I can tell you're like me, you want all of your plants to do double or triple duty if possible -- they should be lovely, should smell wonderful, and should be edible also!
I'm no expert on lotus, but I have not heard of fragrant varieties. Texas Water Lilies doesn't mention fragrance in any of their lotus descriptions (and they do mention it for a good number of their hardy and tropical water liles).
Whoops, I stand corrected (sort of). Our native Lotus is described in PF as being fragrant http://davesgarden.com/guides/pf/go/32227/ but also as being thuggish and/or invasive (yes, it's native, but without its natural competitors present in the ecosystem it gets out of control). Seems it won't bloom in a "smaller" 18-22" pot, so it's not a candidate for container gardening.
Lotus leaves and blooms are both really wonderful, worth making space for a water garden container IMO even if they aren't fragrant. (Sure would be nice if they were, though!) I think I've read that the tubers are edible, though... LOL