Galleon is already flyable as a pilot, just isn't very terrifying cause the guns have been nerfed to heck. Engineers having pilots tools would be pointless as they'd be more apt to using guns, not piloting. That would just encourage more engineer pilots which is a disgrace imo.
Think ultimately for it to work you'd need tool/ammo restrictions. Like along with it, gunners get to use all the ammo types, Engineers only get half that. Gunners for engineer tools are limited as well. So...
Engineers say wouldn't be able to use...hmmm...Loch, Incendiary, Lesmok, and Charged rounds. You know the special ammo types which bring either extra power or distance to the fight. Engineers would basically get short to regular range ammo types.
For Engineer tools, Gunners would say be limited to Mallet, Wrench, Extinguish. That gives Engineers the quicker rebuild option and advanced firefighting skills.
Pilots...Wrench, Spanner, Extinguish. Pilots would be quick on rebuild but weak on overall repair.
Do a similar lock up for pilot tools. Pilots get full access. Engineers and Gunners get restricted access.