Desktop Buying Suggestion Wanted !!?

The 7th Gen Core i5 may or may not work on the z170 board. The reason is the BIOS may need to be updated for the board to support the 7th Gen CPU. The b250 or any other 200 series board is a safer bet. There is really no difference between the 7th and 6th Generation other than the 7th having higher out of the box clock speeds.

The z170 board would go great with a Core i5-6600k if you are willing to overclock it. Otherwise if you're buying a locked CPU then you don't need a z series board. Other than that I don't recommend the Core i5 to anyone because the Ryzen 5 1600 is a better pick overall. The only area the Core i5 has an advantage over the Ryzen 5 1600 is with single threaded performance and you need a higher clocked Core i5-7600k to achieve that. In multi-threaded performance the Ryzen 5 1600 handily beats the Core i5.

Some Asus motherboards do have a BIOS flashback feature like the Maximus line. If you bought a Maximus 8 board and a 7th Gen Intel CPU, you could flash the BIOS to a updated version without needing a 6th Gen CPU.

The RAM should work but I've had better luck with G.Skill brand RAM.

EVGA is preferable because they have the best warranty support. I've had or have Asus and MSI cards too and none of them have failed so far but I trust EVGA more.

The AMD Ryzen line would probably be a better option for you. You really can't go wrong with a Ryzen 3 CPU for many reasons. It works great with graphics cards like the RX 580 and GTX 1060. AMD socket AM4 motherboards will support upcoming Ryzen processors that havent been released yet whereas Intel 200 series boards won't support the upcoming 8th Gen Coffee Lake processors. This give Ryzen an advantage in futureproofing your system.

https://pcpartpicker.com/list/LPkBCy

If you're willing to overclock, the CPU is the same thing for half the price. And the GPU is almost twice as fast at stock.