its not good to keep ur tank lower than half coz it can dry up ur fuel pump can damage ur pump insides. kept it full incase you have no cash lol
i also have a weekend car, r32 gtr.
my everyday car is r31 ti turbo. i love it, it has 4 doors for space, big boot space for baby's pram and stuff, towbar for towing, good on fuel, power to smoke most standard cars including evos lol (full sleeper), full pwr option including cruise for the freeway and easy to drive so my wife can drive it coz we share the car.