It seems you really don't understand that on-paper specs & numbers do not matter at all.
Anyways, here is the explanation:
1) Iris scanner is not at all a gimmick. This has been proved in lot of video reviews (I hope you have watched most of them by now) by some famous YouTubers. It works flawlessly & the useful scenarios for Iris scanner would be when your fingers are wet (or home button) or do not want to make that home button oily (like when you are eating food). This is when Iris scanner would definitely come in handy.
2) Snapdragon 820 is quite a powerful chipset & no users are experiencing any issues (except those from mobile carriers like T-mobile, Verizon, etc. because of their useless apps that come with the phone). If more performance testing / stability testing is needed to be done for a better experience to the end user, engineers at Snapdragon know better about this & you can expect next version of this processor (821, 823, etc.) in the upcoming smartphones.
3) 6 GB RAM is really a ridiculous idea. Don't know why people give importance to numbers without understanding the technical know-how.
Android handles RAM in a different manner & sadly, more than 70% people compare it with Windows RAM management system. 4 GB RAM is enough for a smartphone & moreover, unused RAM is wastage in Android world.
4) Water resistant is nowadays important (at least in tropical countries where it rains frequently & unpredictably). Moreover, you never know when your phone will get wet due to water spillage, rains, storms, etc. Now newer phones (other manufacturers) in the market are also making their phones "water resistant" but you cannot use those if the display is wet because the touch won't respond properly.
Well, now on Note 7, with the S Pen also designed for water resistance, you can seamlessly carry on with your work, with full & functional touch response from the display, regardless of whether your fingers are wet or display is wet.
Conclusion: Don't just ridicule a smartphone just because the numbers are important & these "other manufacturers" are offering "more" (useless) RAM.
The real-world usage, statistics are more important than these mere numbers & Note 7 is a beast in all the smartphones right now.
Now for your "real question", Note 5 is also a great device, you may or may not upgrade to Note 7 immediately (just because it is costly right now, no other reason not to upgrade). Maybe you can decide after 6 months; by this time, the price would have also dropped down a bit

If investment of money is not an issue (and you are desperate to get a new phone), then definitely go for Note 7