For the starters in my opinion I would get at least 27" monitor 144hz.
Get this thermal paste instead
Gelid Solutions GC-Extreme
http://www.amazon.com/Gelid-Solutions-GC-Extreme-Compou...
Also very sturdy gaming mouse pad so your new mouse can nicely glide.
144Hz monitors are kind of a ripoff right now. You pay at least $300 more for the same display if you're going that route. And I can't emphasize enough how much accessories like thermal compound and mouse pads are wastes of money.
You can't really go wrong with either configuration, both have some really solid parts. But I will tell you that you are wasting money on the thermal compound, case fan, and even the Wifi adapter. If you can use the hard ethernet port on your motherboard that will be much better than using wifi for a desktop.