Why not try to mine new altcoin which is low difficulty other altcoin is getting difficulty increase because more people are mining just like bitcoin the more people enter to pool the difficulty increases but its still profitable since the price of altcoin is getting increase the the profitability is there depends if what mining rig you build..
why not pick 10 new ones at 1 dollar a coin and just buy 100 bucks worth of each one.
Yup, it's totally dumb to mine a cheap coin even if it has a promising future.
In the end of the day, you will have to pay an electric bill much higher than the price of the coins you mined.
It is getting off-topic, I remembered that I already answered the OP.
Here