if u ask my opinion if u want to do long term investment then u should go for monero or Zcash....this currencies have lower market capacities and monero is quite a famous currency too so probability of monero is highest after bitcoin.... ones bitcoin hits a higher values people will look for alternate ways....Investing in the currency is more like investing in collectible people r buying them coz there are less of the out thr if i had alot of money i would buy something rarer than something with alot of market capacity....If ur a long term investor u should know the meaning of increasing demand thats the main thing happening in the market right now it will sure make few currencies reach top of the market..