There has been a call to bring us the Shaak, since it figured rather prominantly in a sequence of Episode 2. I personally love all the beasties of Star Wars and have been a staunch proponent of giving as many as possible the toy treatment.
While I would buy the Shaak, and think one should be made, I would like to champion a few beasts that cry out more for toy treatment and may be better received by the Sith Infiltrator contengent!
The Aiwha - This magnificent creature has supplanted all others as the creature most in need of being the next Deluxe Beast. I can't thank Hasbro enough for producing the incredible Acklay. Now it is time we had an Aiwha with Kaminoan rider.
The Orray - Well, this one is a bit of a given. The mount of the Geonocian Pikadors in the Arena. I think that it would be preferable to have the beast come with the chariot in favor of a pikador mount. Or possibly give us both a rider and a chariot for the captives.
The Ikopi - These massive antilope may well be just the right size to slot nicely into the Deluxe Beast line. Throw in an ARTICULATED Mott and we have a great set that reflects some Naboo wildlife.
The Deluxe Saga Beasts - I propose a Deluxe (carded) set consisting of a mynock (improved version), a Swamp Flyer (with articulated wings that can be moved in a "flapping" motion, a Scurrier (or two), a Naboo bird, and perhaps another smaller creature.
The Jerba - Well, it has it has it's back to you, but it does appear on screen. The Jerba is a horse-sized creature and might also make a good Deluxe figure, perhaps coming with either a Jawa or at least some kind of Mos Eisley-esque prop.
The Eipie (reprise) - Rerelease the Eopie, this time with the cargo sledge used to carry the parts from Watto's shop to the Queen's ship. If Hasbro feels they have to include a figure, give us Kitster!
That is about it, as Hasbro has given us many a beastie, but I want them to give us that many more!