1) Don't try and line things up. Just go "It's comics" and accept the floating timeline into your life. They're written by different people, at different times, without a set time, and aren't written to be lined up with strict timelines. Just accept that it's early after the New Avengers form, but before Civil War.

3) By publication date, Rumiko dies during Avengers Disassembled, so it's a little hard to say. Floating timeline.

4) Oh yes. Lots of scars. And an artificial heart he has to recharge. One that a sentient version of his armor plunged into his chest. It's...very creepy.