I seriously can't understand why a Dragon/Fire dual-type Pokemon hasn't been made yet. I mean, when you think of Dragons in mythology, etc., you usually imagine them being able to breathe fire. So, wouldn't it make sense to create a Pokemon using that type combo?
Also, going on the topic of evolutions again, there are way too many Pokemon in dire need of an evolution (Pinsir, Luvdisc, etc. etc. etc.). Give people an actual reason to use these Pokemon in competitive play, since right now, I seriously doubt if anyone does. They don't have the stats or movesets to be useful.
There are a lot of things I'd like to see in the 5th gen games; probably too many of which to list. I might get to it later... maybe. =P