What do you recommend and why? Is it better to invest $10K in 1 potentially profitable alt coin or in 10 potentially profitable alt coins? I'm not talking about already established alts like ETH, XRP or DASH. I'm talking about investing in relatively new, undervalued alts with great potential.
It depends on your own preference for risk vs reward.
If you want the highest potential reward and are prepared to accept the highest potential risk, then put it all on one coin. You might make a huge profit or you might lose everything.
If you want to limit your risk, then spread it across multiple coins. Then if one of them moons you will make a good profit, and it doesn't matter if some of the others fail.
Personally I spread the risk. But everyone has their own preferences.