First, let me say that I do not approve of your tone, even though I find your vain attempts to humiliate your discussion partners mildly amusing.
Now to your post.
Its the weight of two printed books. If you want to carry that kind of stuff around that's your problem...
As I already mentioned, this is an argument I don't buy. Maybe for people with weak eyesight.
If you care about sound quality that much, you will have good earphones anyway. Hard drive capacity is a good point, but that is the nature of SSD-based machines. Of course, if your line of work involves handling large data, then I see how this can be an annoyance to you. Upgradeability... that word again

16GB RAM is the maximal amount you will be able to tup in those laptops... and storage can be expanded externally.
Well, then let's get constructive here. What are the features you would want of a workstation-class notebook? The only thing that comes to my mind is a workstation GPU and maybe a more generous internal storage space. Workstation GPUs only make sense to people who work with 3D graphics, and if their work is that intensive, they will get a proper desktop based workstation instead. You seem to be an audio professional, so that feature will be completely pointless for you.
This was not my argument

My argument was that there is not a single thing that 17" model does which would put it above the current 15" lineup. Storage can be an issue of course for some people, but its not specific to this debate - its rather part of the general classical vs all-SSD architecture debate. I see this debate slowly dying once Apple rolls out its PCI-e SSDs in all models - which will give you storage speeds which are impossible to achieve with a standard SATA-3 drive.