In terms of returns what digital currencies do you predict are in the running for a podium finish in 2019?
Top coins but not specific, since every coins have the potential to pump high this year but 10,000% profit is not possible even if its bitcoin. Try to invest without expecting any return like this because you might be disappointed. New coins can go as high as 100% increase on their value but very few of them succeed on that one.
within a period of one year, I'm not sure that the coins in cryptocurrency can achieve such high price changes.
except for small coins that occur in price manipulation. for top coins, prices may increase several fold in one year, but not that high
So it is better if we can have so many coins that might give us profit in the next bullish market than only have one coin because as you said, it is difficult to make 10,000% plus of profits. I think the biggest profit we can get in this year will be around 30%-50% for one coin only and maybe the price can double the price now. But still, it is hard to get more than 100% or more if the market is not getting any big wave from all traders.