Xeon E3-1535m should be better and higher the RAM more efficient it would be.
You can refer this link for the requirements : System requirements for Adobe Lightroom for Mac and Windows OS
I don't think you'll notice a difference between 32GB and 64GB
In your opinion, would you opt for the:
i7-6820HQ and 64gb RAM
Xeon E3-1535m and 32gb RAM
The RAM/processor are roughly $300 to upgrade so trying to figure out which one will have the most impact (if I were to only choose one).
As I said you will not notice the difference between the 32GB and 64GB.
As for the question about which CPU to get, I can't tell you how to trade off speed vs. money spent. It's your money, you have to make that decision.
Sorry, I will rephrase my question:
Xeon with 32gb RAM
i7 with 64gb RAM
The cost is the same.
I guess that the advice to stay at 32GB ram isn't being received by you. So I decline to advise on the specific question you are asking.
Got it, thanks.
I will wait for anyone else to chime in on the processor.