First as an overall adjustment, we will be revamping the difficulty of increasing parry skill. After this, the next step will be skill adjustments for each class.
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Parry is a difficult skill to level, that can be agreed upon by most. Guard, as it stands, it harder. Parry can be skilled by any job that can equip a weapon OTHER than hand-to-hand. Even MNKs and PUPs can gain parry.

For Guard, you MUST be using hand-to-hand. If I recall, the only jobs that get Guard skill at all are MNK and PUP (I could be wrong! Don't quote me! D=).

Guard is, in my personal opinion, harder to skill up than Parry for that reason alone.

You must also be tanking, and have to pass through several checks before it gets to Guard, which I believe is the last check before taking damage (Again, don't quote me.).

Since you guys are looking into Parry, what about Guard?