i assume you do not know a lot about ffx.
Yuna's overdrive is one of the most useful overdrives,for it grants you the opportunity to use an aeon's overdrive without having to wait for it to ''grow''.
Also,Yuna does not have a weak physical attack by nature.
A friend of mine has grown her strength so much that you can see Yuna toucing a monster with her tiny staff and cause 99999 damage.Therefore it's what you make it.
Yuna's overdrive is not only useful,but a most useful one.