1, is the rubber seal damaged and getting trapped when shutting the boot?, this might explain it being hard to close gently, check this first as its the easier option...
2, adjustment is wrong on the catch
dont think the loop on the floor is adjustable but the catch on the boot lid should adjust slightly,
normally 2 or 3 bolts to slacken and move the catch
downside would be that you could create a gap which will cause the boot to rattle, thats more annoying than having to slam the boot lid shut
move the catch as much as it will travel to see if it then shuts without slamming, then move it slowly back, tighten the nuts, try shutting again, adjust until you are happy with the closing then road test to see if you get the rattling long job but be patient,
It may be that nothing needs adjusting
My new Note had this issue and I took it to the dealer. He said they'd noticed this with all Notes and said it was caused by air pressure preventing a soft close
He demonstrated this by opening the rear passenger door and lo and behold the hatch shut really easily
I was concerned at the time I might damage the lock but have now got the knack of closing it easily, as well as big muscles!