Good sensors yes, and yet they consistently sell less than Canon...
sales ≠ superiority
Longevity maybe (beta vs vhs?)
If Nikon could actually build a decent body, with decent ergonomics and UI to put that sensor in, they could become a threat to Canon's market position.
Nothing wrong with Nikon bodies, ergonomics are different, not necessarily inferior. Canon isn't necessarily the superior one here either. I really prefer my Pentax K52s and D800 ergo to MOST Canon's. OTOH, I can't stand Nikon's D600 or D7x00 series ergo.
Have to agree about the UI tho, looks like someone who can't speak english or think clearly put together the darn menus in most of their cameras... They're nowhere near as intuitive as other mfr's UI like Canon, Panasonic or Pentax.
Although they'd need to work on their lenses too, the only shining point in that lineup is the 14-24/2.8, admittedly great, but beyond that they don't have anything notable.
Really? the 14-24 is pretty good but has its flaws.
note the performance of the recent 70-200/4 VR, it's PDG!
Again, their lenses don't always perform the same as Canon's, neither do Pentax. That makes them more different than anything. I've found that all 3 major mfrs have very good lenses and some that are not so good.
It's not all about ultimate sharpness and lack of CA, those are very important, but so are appealing bokeh and little details like (micro-)contrast and handling.
I do not think your anti-Nikon arguments are solidly conclusive, they're more like your personal opinion.
Which you're entitled to express.

Until about 2 years ago, I would have been inclined to strongly agree with your opinion.
What a difference a gear (change) or 2 makes.
And nikon lenses mount funny. 
I'll give you that!

2 CW systems and one CCW that I use, the Nikon way to mount lenses just feels backwards.
but it still holds the lens on.