Id say if you want fun fwd for $12k buy a nice (hard to find) srt-4.
BUT, thats not what i would do by a long shot. For $12k you can get damn near anything, seriously. If you care about driving in rain and snow, buy an awd!
Buy a turbo 5spd subaru baja. If you're lucky you can occasionally find them for 12k, they're pretty quick, awd, ground clearance, a truck bed, and the sti aftermarket. They're omni-awesome.
but if you want fuel efficiency and fwd id buy a late 90s civic vx hatch for 3-6 or an early 00s insight for 6-10... but not much fun there.
neon r/t is a safe bet, they're fun, cheap, and get great mileage.
I dont know how you didnt have fun in a mazda 3, honestly..