I am however he is utterly useless and was chosen by my employer. I'd walk in more confident knowing I have the info I need from this community

For context I did not have an interview for AOS back in 2011 so I can’t speak from my own experience.

They will probably only look at 1 piece of ID, but taking it all can’t hurt.

The picture you posted says “may” not “must” take a lawyer, so my guess is this is for applicants who don’t speak good english or have other issues.

For the medical the picture you posted says unless submitted in the last year, so if you already submitted one in the last year you should not need anything else.

They asked for “all travel documents” at the end of the Citizenship process as well, I feel like they just want to get any official documents they can so they are not repurposed by anyone, I assume they are just destroyed.

For the last question, my read is they want the original and a copy of any documents you have submitted copies of before. They will want to compare the original to the copy and then keep that for the file. At my Citizenship interview he actually scanned everything in from the originals rather than taking a paper copy.

The job offer is still important, while you are already employed this is a new application, you are not moving from a L to GC, the process is independent, I think the supporting letter with mine said that I was already employed and that the Firm would continue to do so. I would get a fresh letter to take and/or I would take your last few months pay stubs and most recent contract so that you can prove you are still employed in the same job as the I-140 petition. I would check with the lawyer before accepting any promotion before the interview. If you plan to go for Citizenship you also need to consider this, I have only heard about it in the context of changing jobs after receiving the GC, but have heard that it can raise questions at the time of applying for Citizenship. If you search other forums people will say to wait 6 months or a year, but there is no official policy I have seen, the lawyers take was that they could question your intent at the time of getting the GC if you moved to soon afterwards.

We have no idea how different it is, enough that you mentioned it here, don’t assume that because you see a job as “better” that someone else would see it like that, does the title change a lot? e.g. if you came as an L2 with specialized skills and then were promoted to a different job where you only managed people and did not use that skill they may not view it the same way as you do, or made a move to a different state etc . It sounds like things have changed anyway, Neill had pointed out a new form: I-485J maybe look in to that, my comment was related to something similar but different, moving between employers. I would have your employer confirm with their lawyer it won’t cause issues if it was me.