That's right, Ethereum LiteCoin and Bitcoin Cash has the most influential Altcoins in the Market today.

for now i hold ETH and waves, both altcoin always give me a big profit. wherever i trade those coin in many exchange always lucky. maybe those my lucky altcoin for me .

i think  ETH and waves is a good choices for now, my advice is not to follow other people's choice, as good as any altcoin it will not necessarily give us an advantage if we do not know more about altcoin. first understand the character of altcoin we want to invest . then buy and hold them when it is convinced..

I choose eth and bch for long-term investment, because I think this coin is very strong, if eth from day to day mining results are getting less, but if bch supply a little coin, then there is a possibility both of these coins will be high price in the future

good altcoin for investment right now is XUC and GVT, because I'm sure when this project goes the price will go up and it is great for long-term investment.

litecoin will follow in the footsteps of bitcoin (on a smaller scale) its among the most known coins and people who find bitcoin to be to expensive quickly turn to litecoin because it's among the only alternatives on many sites; It increased more then 40% in the recent days after being stable for a long time, and i'm sure it will increase much more when the people who are new into crypto start researching about other coins then bitcoin and find out about litecoin.

I bought 3 litecoin for 250 euro 5 days ago and right now it's already 350 euro; get in on the train before it's too late, 2018 will see a similair rise to litecoin like happened to bitcoin  

Recently this month there are 2 altcoins that rise and shine like a rock star namely: IOTA and Cardano

IOTA :
market cap : $13,943,541,460; value: $5.02;   trading volume: $970,195,000; circulating supply: 2,779,530,283 MIOTA

CARDANO :
market cap: $3,013,944,169;   value: $0.116247; trading volume: $67,467,300; circulating supply: 25,927,070,538 ADA

this is a good buy this month and hold it for 1 year for better growth and gain potentials.

altcoin which will be constantly increasing for the next 3 to 6 months which I believe are Etherium, waves, then nxt,
it is a coin-coin which I think will continue to increase in price even though it takes time

I would say IOTA, but I sold it today, could not resist the profits. Also I like and invested a lot into ZEN (I like their securenodes).