I only have one comment, that I continue to make.
Your MAF readings appear WAY too low, a sign of a severely compromised MAF.
At this point I would like to see a 10-20 minute MAF & RPM graph. Heck, you really do not even need to graph the MAF if you cannot get the MAF reading much above 30 Gram/Sec even slightly spirited.
I took my E46 out tonight with Torque on it and pushed it pretty hard and was easily able to get the MAF to read over 100 Gram/Sec while still under 4500 RPM probably in 2nd or 3rd gear.
The main thing I want to see is where the baseline Voltage of the O2 sensors starts out. If your SAP is still not working, your O2 signature will not be what I am expecting.
The only other thing that could be a factor that these tools will not really tell you is if you have an exhaust restriction, plugged Cat's but this will likely be a long shot and you can confirm this with a $40 Amazon tester. But someone would have to really abuse the car to clog the Cats.
Forget about your fuel economy at this point, this will be resolved once you get everything else in line or you can focus fuel economy once the basics are working correctly. This is really the last thing you should be worried about.
The SAP not working can even impact fuel economy a bit as the O2 sensors take longer to warm up and the engine will stay in a fixed open loop warm up enrichment longer than it would with the SAP working properly.