Yes, it's a bit weak.

Bard has more raid utility, and can do more damage. At the very least it buffs party members a lot. Machinist should do a considerable amount more dmg than bard cost of less utility (since it already has less utility)

Add 10 potency to each heated shot, buff hot shot bonus, and make flamethrower not weak. AND make wildfire 15 seconds. 10 just isn't enough to do all the things. Procs, critical clean shot, hyper drive, rook overdrive, etc. 15 seconds would be a great help with DPS.

If you think about it, machinist uses guns. Probably the most damaging weapon in real life comparing in game weapons. Why would it be the weakest dps!