See... here's where I disagree with people. The system is designed to work for both. You can store up to 99 leves on a timer, and that timer ticks for everyone -- long session or short -- when you're not using the points. There's an increasingly huge amount of stuff you can do in game, you're not -always- going to be doing leves.
I started playing Rift this weekend because a friend of mine gave me a copy for free (its nice knowing Gamestop managers who get baskets of free stuff from conferences...), and it took like 2+ hours of game play just to get out of the tutorial area. That's all well and good, but honestly, I have a lot of games on my plate (Dead Island, Magic Online, Minecraft 1.8) for video (starting a web series) and entertainment purposes, it gets to be a bit of a headache when developing my MMO character requires I completely disregard every else I want to do in a 5 hour span.
There's going to be tons to do in FFXIV once it gets going full steam, I think this system is less for casuals and more an attempt to make something that'll work well for both sides. After a short, week-long business trip after unlocking Abyssea in FFXI, I never ran out of time stones and they work more or less the same way as here.