A MNK is kinda crappy i feel..besides Focus there is nothing good about it.

A SAM/WAR and a SAM/RNG(with a PROPERLY lvled archery) is a good combination by far compared to a MNK sub.

SAMs do good dmg at first, and can somewhat tank low lvls before 30, afterward, they are skillchain masters and trick attack buddies. Third Eye makes Trick Attack more viable/safe, and Meditate gives you more TP and gradually increases unlike when it is subbed. They as they go higher, have bad accuracy, and need to focus on Acc/DEX gear. It is also recommended to have a Skillchain chart ready at all times, and you need to know your Skillchain/Monster Element well to be a prime SAM.

Their power will lack at later levels, but fear not, a SAM does not do dmg on its own, but relies on their impressive TP gainage, to do more Skillchains ever battle, and therefore more Skillchain, more Magic Bursts which deal the bulk of the dmg. So they ultilize their abilities and cooperate with other party members and do more dmg that way than directly doing dmg. A good SAM, is a RDM with TP Refresh and a heavy hitter(in terms of Skilchain/Magic burst total dmg) in its own respect. A well-trained SAM, is formidable.