I'd have to say that indeed as far as FF lore goes, most people associated spear users with Dragoons/Lancers. Even Samurai was stretching it, seeing as the spear was more of a secondary weapon since samurais in past FF games exclusively used katanas and/or great katanas.

Therefore it's hard to imagine anything else than Dragoon. The team behind FFXIV isn't limited to past jobs though, they very well could invent a new one.