Alas, with the Note 5 you GIVE UP both 1) User Replaceable Battery, and 2) "External Storage" (micro-SD card slot).
........
This is a good point but it has to be a matter of personal preference. A few years ago I would have agreed that having expandable memory was a must - however, I have fibre broadband at home and unlimited mobile data so every photo or video I take gets uploaded to the cloud the day it gets shot. I'd have to do this (eventually) regardless of how much memory I had so for me it's easier to just do it every day.
As for the removable battery there's no denying this is a plus. However, again personally I'm never far from a power outlet and also have a 10000mah portable charger and this thing charges FAST. I guess there's also the issue of the battery degrading over time but in all honesty I don't keep phones longer than a year, although this Note 5 is so good I'm hoping to keep it much longer.
Absolutely agree with your comment on Personal Preference, within which I would include the Intended time of ownership.
Our preference is to (hopefully....) buy well, and keep things until they no longer perform their function. In the past, we carried separate PDAs, and our phones WERE swapped out at around the 2 year mark, because our carrier provided an incentive to do so (or, at least, FAILED to provide an incentive NOT to do so!), however, that has been changing, with carriers (in the US) trying to separate the Cost Of Service from the Cost of Device.
Currently, we save $75 / month by NOT taking a "Subsidized" Phone (3 lines) - which makes a nice incentive to keep our devices for as long as they remain viable.
This goal makes a Replaceable Battery a desirable feature: the batteries in ALL of our mobile devices has been the first sub-system to show signs of reduced function, other than in cases of Accidental Physical Damage.
Admittedly battery technology has changed over this time frame (going back to the age of "Hand-Held Computers," Monochrome Laptops, and through Palm, Handspring & Dell PDAs) - but my wife ended up with a Note 4 because her still-rather-new HTC Android (within 2 years) developed a flaky battery AND she ran out of internal storage - and she did not want to risk either event when choosing a replacement.
And - sadly! - we do not have Unlimited Data, speed throttled or otherwise... :-(