So, who here liked the medals in B2W2? I sure did! They gave me more of a reason to accomplish a lot of things because I've always loved to collect little things and rewards like these in video games. Because of this, I'd love to see a medal box in X and Y as well!
There should be medals for certain achievements that we didn't get in B2W2 though. Like seeing/capturing a certain number of Pokemon in the Pokedex, for example. I'm surprised we didn't get medals for that, though there are medals for catching all Pokemon of a certain type in the Unova dex. I also like the idea of medals for catching all Pokemon from a certain region. Like a medal for all Kanto Pokemon, a medal for all Johto Pokemon, etc.
And just like each new generation adds new Pokemon, gen 6 should add more medals! There are 255 total right now, if I recall? Then adding 100-150 more at the least should do fine. ^^