I do know that DL offers the economy comfort seats to nonrevs if those seats are available. They have been very popular (and a source of revenue), according to tripadvisor forums, but I see nonrevs getting them often.
FYI--DTW/NGO/MNL went out today with all employees up front.
I thought your inquiry was about your wife--what does your size have to do with the OP? I'm getting confused