Engineering seems to be pretty underwhelming past rank 5, Tactical past rank 4.
Gunnery feels overpowered compared to Piloting, considering the Pilot also gets benefits from Gunner skills but not vice versa. If you want to be a Pilot, you're forced to also level Gunner. Think about splitting them a little bit - adding Pilot skills that power up the Pilot turrets, and making stronger Gunner bonuses exclusive to Gunner turrets. Damage+ while drifting should honestly be in the Pilot tree, not Gunner.