1) They can be as shiny as you want, depending on preference and what you want to refinish or oil them with. Both of my pairs of walnut OLAs by default have a "satin," as you described, finish.
2) Not sure if there's a way to "re-plate" the inner trim, but those don't look too off from the examples I've seen.
3) As long as the voice coil isn't rubbing, you should be okay. with the surrounds as-is for now But I would definitely refoam them in the proper (reversed) orientation to fully enjoy them as intended when you get to that point.