> Windows laptops are out of the question, and pure linux laptops (until only very recently) were of marginal support and low battery capabilities (especially "close it and stuff it in a backpack for 3 days").

Dell has sold laptops with first-party Linux support for nearly fifteen years, to say nothing of other smaller OEMS.

As for the battery issues during sleep: that actually has to do with a combination of the BIOS settings + downstream ramifications of secure boot (and how the old-fashioned "hibernate" used to work). Unfortunately, that isn't specific to Linux. My MBP has the same problem, and so do the same laptops running Windows.