It is ALL preference. I have blues and all that "for gaming" is pretty much bs.... It depends on what You like. Do you like noise? Do you like to feel a bump? Do you like a low actuation point. I suggest go to a computer store that has different types of switches out and try them.
Yah. Mining isn't really a "hold thing". But Litecoin is good because the price goes up hand by hand with bitcoin (for the most part). Mine a multipool that pays out in LTC?
For fun yes for $. Kinda. You won't be getting any type of ROI if you buy a system specific for mining. But since you have cheap electricity, you can buy a Scrypt Asic.
Most coins go down after launch. EX Silk,White,Asian,Aurora,Vert,Mint,Shibe,42. My best bet is to invest in a coin @ ipominer.com and hold for a month. Then sell.