Now see...the idea of an ability with such a long timer is outdated in this day and age. Back in XI, before the advent of WoW, it was made to where you're only doing like 1 or maybe 2 contents a day, so the meticulous planning and utilization of 2hr abilities fit there. Fast forward to present MMOs where the typical approach to content is to grind them or otherwise repeat for an extended amount of time. Having 2hr or even 1hr abilities really would put an artificial restraint on the amount of content you can do in any given amount of time. I think the 15m abilities work well. Not overpowered, but not weak...there in a pinch when you need it 1-2 times per content.