@Noel_Kreiss: It's actually because of the Ace battleback format. All of the possible battlebacks have a very limited field of view, so any side view system unfortunately has to look "straight" as there isn't a lot of room to position the combatants without them "standing" on the scenery.
@GamingMitchell: As I'm switching from a front view system when the game's already about 60% done, I needed battlers that somewhat resembled the ones I was already using. There are always some analogues in each RM's RTP, and the RM2k3 battlers are very easy to just slot in as the monsters I've already made.