You wouldn't have to worry about Cress, as she and Porygon-Z were recently voted BL (my question: anyone know exactly when that takes effect on Shoddy?).
Lucky you don't, too, as Cresselia would survive just about anything Torterra could throw at it and demolish it with Ice Beam.
Also, just another note, the Latias suspect test isn't quite finished yet. It may end up Uber, or it may not. I recommend following the topics where suspects are discussed (I did for Raikou and Froslass in the UU forums); it gives you an idea of just how much thought goes into the tiering process and just how valid both sides' arguments are. I personally don't like Latias in OU, as I think the centralization around Dragon and Steel it caused is awful, but to call it retarded is just ignoring the entire suspect process.