Chosen Solution
I repaired my 6S+, replacing the screen and battery, along with a new layer of adhesive. The disassembly, repair, and reassembly was easy, and I was pleased to have the phone alive again. Perfectly. After two days, it failed. Black screen, not recognized when plugged into computer via lightning port/USB (using known good cable). Haptic response when someone tries to call, but otherwise goes to voicemail. Tried reset. Nothing. I am going to put my old display back on to see if it will work, but before I crack the case I wanted to get some additional opinions on recourse. Thanks in advance for any contribution/thoughts/moral support.
Update for reference: I re-seated the connectors for the display and powered it back up. First test, prior to pressing the screen into the body, looked good. I lowered the screen into the body and it was fine for a minute, then very slowly the screen dimmed/smeared until it was black and no longer responsive. I then lifted the screen from the body, disconnected the battery, and reconnected the battery, and the screen came to life again. After several minutes, the screen gradually dimmed/smeared grey then faded to black. I removed the new screen from the phone, removed the button from the screen, replaced the button onto my old chipped screen, and reinstalled the screen. Upon attaching the battery connector, and doing a hard reset, the phone came to life. I did not reinstall the screen just yet, and opted to let it run to build my confidence. It seemed to work, so I seated the old screen. Needless to say, I am still running on the old screen perfectly. I believe the NEW part shipped by iFixIt was faulty, and I will look for RMA options.
