Symbols on both sides, SERIOUSLY.
I would've liked to have seen the G4 style wings on G1 ponies. I think they did a great job on those, making them look very feathery just a like a MLP wing should.
I'd like G4 (and would've liked G3) to have had more distinct SETS like G1 had. With G1, they would show all the ponies on the set on the backcard. Even the mega-sets like the So-Softs . . . If you wanted to know who was in the set, you looked at the brochure or backcard. You knew immediately what feature all these ponies had in common (fuzzy flocking, or twinkle-eyes, or being flutter ponies.)
With G3, it was like . . . all these ponies who were just kind of ponies, and maybe they had a particular feature (like a symbol with glitter in it) but they were never actually listed or collected in one place, not in a brochure, certainly not on the backcards. It totally defeats the idea of "collect them all" when you can't even figure out what constitutes a "set" of ponies. I just . . . ugh. Maybe G4 will do better on sets than G3 did; I hope so.
On the same note, I wish Hasbro would hire artists to do those beautiful watercolor backcards again instead of recoloring and reusing clip art. Yes, it would cost more. But when I was a little girl, those beautiful G1 paintings didn't just make me "want" ponies, they made me YEARN for the ponies they showed. They were so . . . so idealized with their beautiful settings in the clouds or forest glades, and while most of them showed the ponies in their "toy poses", they also made the ponies look alive. Which just made me want them more, of course; more than any real-life photo of a toy could ever have done. IMO Hasbro is actually losing money in the long run by being so cheap with their art.