If you have a large enough portable drive or are saavy with mapping drives you can copy the updated files into the install folder after your initial install to speed up patching. The game's footprint is past 14GB now. A lot of data.

May want to copy your character folder over too. It is under your My Documents/My Games path within a folder for FFXIV. Otherwise you may need to rebuild any customizations to things like HUD layout, crossbars, macros, and chat filters.