Well that's it isn't it, as little as possible I guess. Although even at the lower end of the market £8.49 I can get an E-Blue Cobra 600 to 1600 DPI adjustable gaming mouse, with 6 buttons. I see you're intending to splash the cash on a new rig at xmas and are going with the mouse that comes as part of the package. Are you not considering upgrading the mouse?
I was intending to play on my samsung smart tv. But I'm now wondering if it has the spec to play these sort of games? Then I thought about hooking a laptop up to the tv. But I think that will have the same problem, basic graphics card. It's looking increasingly like I'll be playing on my PC. But without the 42 inch tv, my pc screen is 21 inch, but I still have another tv, the one I replaced with the samsung that's a 32 inch screen.
I built my rig last year at PC Specialists, it took a lot of juggling to get it to come in at £500. I went with the onboard soundcard, because the PC it was replacing had 4 speakers and sub woofer. My graphics card is an nVidia GeForce.