Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
The thing is that there's always a system that can be designed to work around the obstacles that MS present but the sad fact is that we have to create these systems to overcome them, something which most admins could do without.
From looking into it further the Office 2016 PKC's do seem to be the retail product and OEM versions appear to be dead now. Thus, as you say, can be transferred to a new PC on death. Based on that, with the current activation model, it seems a necessity to have some form of internal manual system to track what license belongs to what hardware....sounds like as nice business opportunity for someone!! :-D
I agree that a tracking system would be most helpful and a possible business opportunity for someone. But there are two issues I see. First, many of us are suspecting that MS will soon do away with retail products and switch completely to Office 365 subscriptions. That makes sense given the overall MS strategy. Making a tracking system may instantly prove to be not worth the money it takes to create it, although one might still make 5 or more years profit from it. Second, you have to find people willing to pay for it. The entire reason customers are using Office 2016 retail is to save money. The cost to purchase and track Office 2016 retail with a service would probably be higher than just purchasing it with volume licensing (or going with a free Libre Office).
Given that someone does find a way to profit from this and actually makes it quickly, Office 2007 support is set to expire 10/10/17, when the next group of purchasers will be getting onboard with some new version of Office.
My general question for everyone is, how much would YOU be willing to pay for a tracking system?