I really don't know where people are coming from with this talk of 'higher quality parts' in the MBP. Last time I checked, the MB and MBP are made with the same kind of aluminum... 😕
The only difference in terms of quality are the specs of the parts. Of course the screen is going to be better with less light leakage - it's a completely different panel! Everything else though - the trackpad, keyboard, glass, aluminum, HD, RAM, CPU, logic board, etc. - are all the same in quality. And there is no such thing as better quality control with the MBP as opposed to the MB... both follow the same strict QA standards.
If you think the MB has more reported issues, that's only because more people buy them. I guarantee you that the percentage of defective machines is probably the same for both. And in my experience, I've already seen three defective MBPs and no defective MBs (not that it's a reliable indicator or anything).
And I also think that 'future-proofing' your machine is nonsense. It's no reason to buy a MBP over a MB, anyway. Unless you're a gamer, both are going to be obsolete within 6 months of each other.