Leveling multiple classes is the way of FFXIV, always has been. They've toned it down a little bit as of late making certain abilities class specific. This game is still unique and isn't for everyone. Leveling to get those cross class abilities will give you an edge over those who simply level one to 50. Jobs will take that away to a degree but you'll be given job specific abilities, all you need to accomplish your role as that job though you'll still need to put a lot of time in to do the quests and whatnot to get all the gear/abilities.