you have to keep in mind that a somewhat decent 1080p monitor starts at 100$ while tvs are at around 200 -250$ or even more and every console title you buy is 10$ more expensive. you also don't have big sales like steam sales AND you have to pay 50$ to play online per year, while not much it adds up to what you have to invest on the first time you buy a console.
and what console can play AAA titles at 1080p 60 FPS not to mention high settings with aa on?
as for peripherals, a mouse and key board can be bought for 10-20$ each, a DS4 or xBox controller cost 60$