Judging by your signature, the Mcdonald's Beast's are coming up really soon. Very cool. Manta Ray was my first Beast Wars figures, and I always thought those four guys were awsome for Happy Meal pack-ins.
How bout Slugfest and Overkill? They don't have a gallery yet, and unless I'm mistaken, those are the last two tapes that need galleries. Plus, they just got so underutalized in the show, and got beat by Daniel of all people in the Manga. They deserve some attention.
Optimus Minor doesn't have a gallery yet either. Isn't he the last Transmemetal 2 Basic? And after that, there's Prowl TM2, Stinkbomb, and the guys that Rid Slapper and Darkscream were repainted from(I don't know the names, sorry

). that's missing a gallery, and I think that's it for the TM2's.
Finally, Snapper and Claw Jaw don't have a gallery either. But there's a whole slew of other Beast Wars basics that don't have a gallery either, and the others don't really have repaints of them in the U.S. line, so there's no real "group" there. Well, you could do Transquito and B'Boom, since they were kind of against each other in terms of size and abilities.