16GB DDR4 2x8GB, the cheaper, the better
I never go for the fastest and most expensive, but I always avoid the cheapest too. Yes RAM, even generic budget RAM tends to be very reliable (it is actually hard to find RAM that is not warrantied for life), but RAM from reputable brands, from my experience, more closely adhere to published specs. This means pairs have a better chance of being more closely matched and more importantly, in a couple years should you decide to add another 2 x 8GB, there will be a better chance they will play well with whatever you buy.
I don't see a case. Make sure you get one with lots of large (140mm or larger) fan support, and removable, washable air filters. Filters do not totally eliminate the need for interior cleaning as dust will still get in. But filters will greatly reduce the number of times you will need to break down your system to take outside for thorough cleaning.
I really like Fractal Design cases. Great fan support, excellent noise suppression, excellent design and build quality. The Define R4 (which I have in this system) also has great cable management features. If I were looking for great mid-tower case today, I would go for the
R5, the R4's successor. The new R6 is out, but as the latest, it is still a bit pricy.
Investing in a quality case today will carry you through many years of upgrades. And with the conservative design for the Fractal Design cases, the looks and style will always be in style - if that matters to you. It does to me only in that I pay attention to what's on my monitors and I do not want to be distracted by my cases. I want them to sit discreetly and quietly out of the way, and these do just that. :) I also don't go for fancy case lighting for that reason too. Case lighting for me is just a distraction. And once the novelty wears off, a boring distraction at that.
I used to shun windowed cases as just a frivolous aesthetic feature. But today I would not buy a case without a side window. A side windows is a great "tool" for preventative maintenance. It is simple to just look inside and inspect for dust build up and to make sure fans are spinning. If your motherboard has status indicator LEDs, you can see them too, all without having to remove the side panel.
With your choice of coolers, you obviously will need a wide case. Not a problem with the R4 or the R5.
I also don't see a PSU. Don't try to trim pennies off the budget with a budget PSU. "Invest" in a quality PSU from a reputable maker. Since EVERYTHING inside your computer case relies on good, clean, stable power, make sure you give it to them. I like to say you wouldn't buy your new dream Porsche then fill it up with fuel at your corner Tobacco and Bait Shop. Unlike a car engine which can miss a beat and keep on running, digital electronics will come crashing down.
I recommend at least 80 PLUS Bronze but prefer "Gold" certified for even better efficiency across the full range of expected loads. I like EVGA PSUs.
I also don't see an OS license listed.