Doing the story teaches you the mechanics of the game. If you buy a skip you will be doing a disservice to yourself and cause a lotta headaches. It's not like WoW where everything but raids are tank and spanks. On top of that you'll feel more invested in end game stuff if you played through the story. Also FF14's raids and endgame dungeons are not the main draw of this game though they are very fun. Most dungeons post HW are not as simple as in ARR.