Gargoyles cant use mounts, they can fly however to move at mount speed. Gargoyles can only use rings, earrings, bracelets, and necklaces of the existing items, they cannot equip any other armor other than gargoyle armor, and do not have feet or head and another slot i don't remember, they have a better chance to enhance items, they have inborn knowledge of throwing and imbuing, they have a race trait called berserk which improves offense at the cost of defense when they are injured.
As for templates, id say crafter gives them some nice bonuses, and aside from that anything is fine, except taming, cause they can't mount. Although currently flying doesn't take a control slot, so they can move at mount speed with a GD, or a pack of osterds.
This may not all be 100% accurate, but its close.