Ok one by one I guess.
-Why shouldnt I advance my timing? One of the main thing is if you run crappy gas. If you run 87 all the time advancing it can lead to detonation. While its pretty safe from what I heard and know people running 17degrees and 87 I like a bit of overhead for safety. Another is if you have the JWT cams, they are designed for 15 or less IIRC
-Does the ECU do that automatically? Not totaly. It mainly retards it. Dont think it can advance it further than what you set on the distrubtor. It does modulate the timing when it gets a signal from the knock sensor dont think it does it anytime else really. Ive noticed that timing does retard when the fans come on tho not sure why or whatever.
-Can I safely get more power by advancing mine a bit even though I have the ECU? More than likely. The ECU may need to be reprogramed to get full benifit from the advancing but I not an expert on the ECU. I know very little about them. One of the main things to pick up from the advancing is throtle response. Ive heard that past 17 is nothing but for throtle responce, im not totaly sure but thats what i recall reading so dont take it for the law tho.
-What all exactly does my ECU do besides make me run rich? Im not entirely versed in the workings of the ECU so I cant really explain much. It controlls retrading, how much fuel you need for the air coming in to the engine, stuff like that. You tell JWT what you have and they program it correctly when you add stuff you need to get it reprogramed if its a major part of thats what I understand.
-Is that why my mileage isnt as good? Well thats probaly a couple of things. First thing I would do is the cheap/free stuff. Clean the Thortle body and egr system. See if that helps. Then check the ground on the MAF, not totaly sure the b13's are really bad on that but its always a thing to check. I think its more of a b14 problem from what I have noticed that most people that need to do it drive a b14 but thats just an observation. Last thing is the most expensive check the O2 sensor. It could be bad or going. It is usualy the most common problem for bad mileage. But the most expensive. Check all the parts of the engine also, check plugs, plug wires, cap, rotor button, fuel filter, air filter, look to see if any visible cracking hoses, the pcv valve, just go over the engine. whats you mileage anyways?
As for that comment ben I think its the cams that are limited to below 15, cause most people with the ECU have their timing set at 17 usualy. I could be wrong but will go looking sometime soon.
