NIN has always felt like that, irrespective of raid buffs. If you have roughly similar numbers of actions per job, there's going to be a trade-off between how many GCD actions and oGCDs you have. Having more oGCDs results in a high APM burst. Having fewer GCDs results in a more monotonous downtime once your burst is over. The balance can be gradually shifted over time by adding more GCDs than oGCDs in subsequent expansions, but you'll never get the balance right for everyone.