I'm still confused as to wether or not this is supposed to replace both the Wii U and the 3DS, or if it's mainly home console that can also be brought with you on the go. It makes a huge difference for my prediction.

It will replace the 3DS ouright eventually. 

They'll die-shrink the chip to 10nm or 14nm allowing for the system to be a bit smaller and more battery efficient, and was that comes down in price to $199.99 ... it's hard not to say that's a 3DS replacement. 

We don't know for sure though do we?

We don't know that for sure but it seems inevitable. In a year or two a die-shrink should be possible on the Tegra X1 chip. 

Things come down in price over time too so that's not exactly a shocking thing to predict either. 

If they cut the price, and it gets exclusive mainline Pokemon and Monster Hunter: 50-60 million

If they don't cut the price, and it doesn't get exclusive mainline Pokemon or Monster Hunter: 10-20 million

The price will most likely eventually go down, question is how much and when...if this system starts stagnating after the launch euphoria, I could see a $50 price cut right before Mario Odyssey.

If the system is truly replacing the 3DS as well, essentially being the only focus of Nintendo´s development efforts, a mainline Pokemon is inevitable.

As for Monster Hunter, who knows if it´ll remain exclusive or if it´ll also be on PS4.

That's what worries me though; Wii U tanked right out of the gate yet to the end of its days it never officially dropped below $300. I'm also concerned that if it does tank, Nintendo might abandon ship and make another full-blown portable, or worse, simply keep 3DS itself on life support, so a Switch-exclusive Pokemon, while a no-brainer, is not a foregone conclusion.

Honestly, it all comes down to how Nintendo handle this; if they throw all their chips in like they did with 3DS, it will do well. If they treat it like they did Wii U, it will flop.

Yeah, I agree. There are many variables at this point. This makes it so fun collecting predictions at this point.

it will sell like the wii or ds

That is very different in sales outlook, but strong in both cases. Respect, you have confidence in the system.