Turn depth of field and Ambient Occlusion off. I'm running on a beast system that can almost max Witcher 2 and before I turned depth of field and A.O off, FFXIV was running terribly.

The game is terribly optimized and does not efficiently use the resources required of it. I expect this to change in 2.0 but until now turn off Depth of Field and A.O. You'll be fine after that. Also more cores doesn't necessarily = more performance. You more than likely have an AMD FX 8150 or 8120 which don't run too well on single threaded applications. Regardless, your system theoretically should be able to handle this game fairly well. The 460 is a solid mid range card (on the low end of mid-range) and your CPU is up to snuff. It just comes down to optimization which the current build lacks. The devs clearly recognize this though and it should be fixed with the new engine in place for 2.0.

Again, you could buy another video card but it will not give you that much of a performance boost for FFXIV at the moment due to the optimization issues. If you play other games on your PC on the other hand, I encourage you to buy a 560 or 6870 (or even 6950) if you are looking for solid mid- mid-high range performance.