I'm not an audiophile, so take my comments accordingly.
First of all, I've never been convinced of the efficacy of products like CD Stoplight and Playright Quick Shield. In my opinion these are expensive placebos without sound technical basis to support their claims. But, I know a lot of people swear by them, and I assume you have done your research and decided they are right for you, so I won't try to talk you out of them other than to suggest that you at least test them with your own ears to decide if they really do anything for you. However, I will mention a few other things you might want to consider.
First, be careful with repairing scratches that you don't make things worse. To guard against this possibility, I would make one copy of the scratched disc before attempting repair, allowing the drive's ECC to correct the errors caused by the scratch. That way if something goes wrong during the scratch repair you have at least one copy already on hand.
Second, why are you making the second copy from the first copy rather than the original master? Audio CDs have less error correcting capability than data CDs, so there is some small chance of introducing generational errors. It’s not something I would worry about, but as an audiophile I would think you might be more concerned about this possibility.
Third, why erase the CD Stoplight from the original when you are done with the copy? If it truly does help, why not just leave it on?
Fourth, I don't like labels. They could peel, unbalance the disc or, in the worst case, the adhesive could eat through the protective lacquer on the top of the disc and ruin the disc. I don't think this disaster scenario is likely anymore since label makers have recognized the problem, but early on there were labels sold with adhesives that were not compatible with the lacquer on the top of the CDs. I prefer to label my CD-Rs by hand with the markers specifically designed for this purpose.
Fifth, I would suggest putting some of the recorded discs into a computer drive and testing them for error levels to see how good a job the Marantz is doing at burning the CD-Rs.
Finally, since you will be recording in a stand-alone audio player, make sure to buy audio CD-R blanks. I know, this is obvious, but just in case it slipped your mind...