yeah, 90k interval for timing belt, but it is 7 years so it is good to do it as well, so you can sleep better.
Like HondaRD said, some experience burning when using M1, maybe it is too thin? Depends on whether you use VTEC or if you rev hard. Give it a try and see, but for an auto tranny with such high gear ratio, I think it should be ok.
The B series auto tranny shift hard and clunk, mine did it but from what I heard it is good for the tranny, makes it last longer as it has less overlap between shift. Just drain and refill and it will live for a long time, haven't heard much auto tranny problem on integra in honda-tech.
Couple things you might want to check is the cam seal leakage on earlier model and the cracked heat shield on the header, as well as cracking on the plastic top cover of the radiator. Other than that there aren't many things that can go wrong with an integra at this milage. That thing is literally indestructable.