I played Aion some, but didn't continue after the free period, it just didn't manage to hook me and there's also time constraints these days.
Grind is really not the issue though, don't really understand what is everybodys rush to the max level. They should just make the journey there enjoyable. I guess the problem there is that to be effective in PVP you have to be max level.
I remember back in the original EQ the leveling was nightmare compared to modern MMOs, but who cared, you played for fun, not to reach top level!