My daily driver for 12 years now. 300,000km and counting.
Driving like a grandma (but I do not pulse and glide)
Lowering springs (2006)
Synthetic 0w-30 oil
Synthetic gear oil
Low rolling resistance winter tires (Hakkapelita)
Replaced all wheel bearings
New LRR summer tires - RE92 165/65R14
Upper Grill block
Depowered steering rack; pump and lines removed.
Alternator kill switch (huge mpg gain with this one)
Passenger side mirror delete w/ new large rearview mirror
Junkyard 12-hole EV-6 injectors from a Yaris
Clean airflow around radiator; fill gaps
Warm air intake
Front air dam
Pizza pan wheel covers
Lower grill cover
It's probably a good idea to send the junkyard injectors in to be balanced/flow tested.
Maybe, if I have the time, money and inclination: