I noticed you didn't respond to the point regarding the passengers of American 77.
I may be a fool rushing in where angels fear to trod ... I am not an engineer so all I can do is spitball like most lay people have done for the last 12 years. IIRC, the entire ground area on which the WTC complex was constructed was reclaimed land from the Hudson River. One of the footings/vaults/coffins of either WTC1/2 was cracked after the collapse and the Hudson was leaking in. Again, spitballing, it seemps plausible that the ground area's geological integrity may well have been badly weakend and could have contributed to WTC#7's collapse. Again, don't know about gas lines in the WTC area, but it seems plausible that if present in the WTC area, they could have ruptured and contributed to fires.
I agree that WTC#7 seems disturbing. But I am not even close to considering that it was an iside job by the U.S. Government.