I have played through this game twice now, once on the PS3 and the other time on the 360... my second time I skipped a lot of the branching paths until later on, and it helps to do that since their cost:effect ratio is higher than the main path.

The only problem I had with the crystarium is that its needlessly unintuitive. It could've been so much easier to navigate through but it was made all 3D and shiny for the sake of "looking pretty"