Lack of Bugs, some say? Low number of new Bugs, rather. As far as I can tell, you can cath several of the old Bug types throughout the game, so gameplay-wise, they won't be left out. They were a little on the low end as far as new designs go, but hey, there were plenty of new Bug types last generation. It's not like Fire types in D/P or anything, here the lack of new designs is made up for by a wide selection of existing designs to choose in-game. I feel that this generation, GameFreak wanted to make use of what already existed, rather than making something new just for the sake of making something new (which is the trap BW kinda went into).