$5000 is quite possible but not so fast. I would bet that this scenario could occur in the span of 3 years. $1500 by the end of 2018 is more realistic.
If you expect $1500 by the end of 2018, you should immediately sell Byteball and buy Bitcoin and Ethereum. Bitcoin will cost $50000 by the end of 2018, and Ethereum will cost $5000. You should hold Byteball only if you expect $5000 in a year term.
But Byteball so undervalued comparing to XRB for example, that it can give x3 any time.