preventive maintenance

I'm putting together a preventive maintenance schedule for my blazer and was wondering if my schedule below is reasonable. Feel free to comment on the maintenance, frequency, or let me know if I'm missing anything. Also let me know if you would dissuade me from doing one of the listed items ( one guy told me he doesn't recommend the tranny service). This is just my ideas based on talking to people who are closer to car maintenance/repair than I. I'd like to hear what other people do and how often.

oil change every 3K or 3 months ( whichever comes first)
radiator flush every two years
replace wires/plugs every 50-75K
transmission service ( new fluid, filter, gasket) every 2-3 years or 40K
replace air filter every 30K or so
replace gas filter every 30K or so
fuel injector cleaner (super concentrated) twice per year
replace brake fluid every three years or so

also, is it a good idea to replace certain parts proactively ? Example: starter and battery (every 4 years); water pump (every 4 years); oxygen sensor ( every 50K).

Here are my two cents, although my Dad was a self employed mechanic for 30 years while I am just a shade tree mechanic now. As far as oil changes I understand it depends on how you use the vehicle to determines the frequency. For example shorter stop-and-go vehicle use it is recommended to increase the frequency to about every 2K or 2 months other wise 3K or 3 months is just fine.

Radiator flushes every two years is good, I would stay away from the Dex-cool coolant just because my experience was not so good with it.

As far as the rest of the items on the list I would say they all very reasonable.

Finally, I do not believe in replacing parts for the sake of replacing them. It is sort of like gambling, you’re just hoping to replace the right thing at the right time and spending money on parts that may or may not go bad.

as far as the oil change it all depends on what oil you use also. From what I have seen before on here some people will use full synthetic oil and change it around 15K miels. some conventional oils can be changed around 4500 instead of 3K. so it all depends on what you use and how you drive it also.