Also there is a lv15 hat that gives +5 crit rate. I think the crit rate stat in general is just very low. Whether or not it was designed like this on purpose Idk.

Although I think the formula for determining crit power is a bit OP especially when you add crit attack power materia. This is probably why crit rates are so low.

Crit rate imo shouldn't be tied to any stats in particular and rather should be more based on abilities. Blindside is a good example of this. It allows you to crit when you want to without being too OP. And also makes materia like Savage Might have more meaning. I think this is probably the design they were going for, but unfortunately there just aren't a lot of skills like that atm.