(09-15-2015, 01:06 PM)Aya Wrote: I believe that Astrologian is simply its own class and job, so all you have to do is unlock it with any other class. I'm not sure if there are any important cross-class abilities that are important to have though.
Correct! The only requirement for accessing Dark Knight, Astrologian, and Machinist is gaining access to Ishgard proper through the MSQ! And, as always, they do pull cross-class abilities that could be useful - such as Swiftcast from BLM and Protect/Stoneskin from WHM for AST, or Blood for Blood/Invigorate from DRG for MCH.
As such, if you'd want to avoid any unnecessary leveling on your way to those classes, I'd pick something related to the one you like most and using that as your "base" before switching over. For example, if you want to main AST, go through the MSQ as White Mage - it will get you Protect, Aero, and Stoneskin for your cross-class skills... and White Mage requires Thaumaturge to unlock the Job Quests anyway, which will put you near Swiftcast if you need it. Plus the bonus of faster dungeon queues for quests that require it for being a healer! Flip side for MCH, level Lancer/DRG for its cross-class skills and then switch over.
All simply recommendations, of course. You really don't "need" the cross-class skills - they just either add some utility or help "maximize" DPS (in the case of Blood for Blood). Stoneskin is technically a recommended cross-class for Paladin... but I've never gotten it on Chachan and I still do well enough.