I'm going to be starting a new campaign in the new year, in which the party are crewmembers of an airship. I'm planning to have my character be the helmsman, and as such I have a tool proficiency in Vehicles (Water) via the Pirate background, which the DM is letting me refluff to be proficiency in "Vehicles (Air)".
I would like my character to be an expert with airships, the reason the captain spared me from the noose and brought me onto his crew. However so far as I can tell, the only method to get a greater bonus to Vehicle-related rolls than tool proficiency is via the Artificer's 6th-level feature Tool Expertise:
Starting at 6th level, your proficiency bonus is doubled for any ability check you make that uses your proficiency with a tool.
All well and good, except I'm planning to play a Sorcerer/Warlock; picking up 6 levels of Artificer just to get my Vehicle expertise seems like an awful plan. (And even if I were to play a pure Artificer, the game is starting at level 5.)
I'm fully aware the answer may simply be "no", but is there any other method to get a bonus to handling our airship beyond simple proficiency?