Machinist is actually pretty fun, once you get your Turrets and Gauss Barrel, it works out alot

Promotion Skill is nice especially for DPS needing the TP Regen or heals needing MP regen

People say the DPS falls apart after awhile but Gauss Barrel makes a difference in Damage and DPS.

Reload, Rapid Fire and Reassemble are you best friend for the extra damage.

Dismantle helps Tanks and healers so much because the 5% damage reduction from the mobs.

Wildfire is very interesting due to fact it stores the damage from all the damage you have done and uses only 20% (25% after a certain level)

Gauss Barrel turns from just doing the skills to Casting time, but you get 20% extra damage and you have a very high chance of getting even more from each combo.