Final Fantasy Tactics: Rebirth (FFT: Rebirth) is a modification for Final Fantasy Tactics which features a rebalancing of almost everything in the game, in particular classes but also items, abilities, characters, random encounters, and storyline battles.
You can find a complete list of changes on the features page – located here. The modification in a PPF file is located in the download link below. The current version of the modification is Mk II.
If you are a user having trouble with sprites (character graphics) showing up incorrectly then please try this version (post-patched). If you are a beta or development team member you can also download the full installer.
Here is a short tutorial video on how to install the mod utilizing the PPF version: