I think vehicles now would be more work than needed, all the extra scripts huds and such probably a whole cartload of functions to command them aswell.
but I would like to have useable vehicles in the game at some point im thinking on making. ai lua and more performance work is needed still imo. because now at least the ai drain on the engine is large still, you can see that just by adding enemies in a level that and all the animated plants and tree's make abig hit to fps quite quickly.
evga GeForce gtx 750 ti boost2.0 2gb gddr5. win 8.1 quad core 4gb ram.