I would hold the bitcoin. But now would be a good time to invest a small amount more.

Which is the best altcoin that in undervalued but has a good prospect in 2018? I have invested in power ledger, ripple. Suggestion and recommendations welcomed.

My portfolio is 30% bitcoin, 30% ethereum, and the rest other altcoins. There are good altcoins with prospect and not as expensive as bitcoin. These altcoins are for long term and not for anyone who want to make quick buck. A few of my recommendations are

Power Ledger (POWR)
Ripple (XRP)
Iota (MIOTA)