Small maintenence issues and minor upgrades

[savingraysprivates]

I suppose I should start off by replacing parts that are due to be replaced. I have already done the spark plug thing (72,000), transmission service (60,000), cooling system flush (48,000), timing belt (68,000, didn't do water pump), I put the fuel additives in a couple of times, replaced the air filter when it got dirty, and the routine oil changes.

I need to know if there is any other maintence issues that I should attend to, because I like to be more proactive than reactive with my cars. Also, I was wondering if there were any small performance upgrades that I should do, such as that chocolate chip thing people are all talking about.