Hi, this is my first post, sorry for a long one in advance! I just spent about 2 hours reading a bunch of material on the timing belt change procedure, along with many other threads. We bought my wife a 2004 aveo about 3 or 4 years ago with 70k miles on it. Great car in near perfect condition. It now has 105k miles. Still near perfect condition. I've kept up with oil changes, changed the plugs and air filter once, and plan to do a bunch of maintenance soon. I want to change the timing belt soon, and also the transmission fluid, amongst many other items. I am not a mechanic but am very mechanically inclined and have worked on many cars over the years, just about every job there is to do on a car. I have never done a timing belt on a DOHC engine, however, but think it shouldn't be too bad (seems pretty easy from the very good write ups I've seen here). Here are my questions and thanks in advance for any help:

Timing Belt:
I've read several write ups on here. I have just few questions and looking for recommendations. Is it recommended to replace the idler and tensioner at the same time as the timing belt? Can anyone recommend a kit? I've seen several and not sure if some are good and some junk. Should I also replace the water pump at 105k miles while I'm in there?


Transmission:
I've found that the transmission does not have a "servicable filter". Is this correct? So do I just drop the pan, clean, and reinstall? Or is there a way to take the "non servicable filter" off and backflush it with some fresh fluid? Also what kind of fluid does this transmission use?


Other things:
Does this car have a serviceable fuel filter? If so where is it located? I have quick disconnect tools as I assume it uses these type of lines being a GM.

Does this car have a pcv valve? I can't find one but if it has one would like to change it.

Thanks again, sorry this is such a technical filled newbie post! Want to try to keep this car running great. The only issue we had was a few months ago the plastic thermostat housing broke, good thing the wife knows to pull over when the temp rises! $60 later for an autozone non plastic thermostat housing, and good as new!