I think one of the promising altcoins 2019 will be Elastos or Fusion. 2 this is really a great project with a good future.
The recent market is temporarily down so we don't predict the future possibilities of nee project. I think old altcoins only make sound in future because already many investors and companies are adopt some altcoin so they only occupy the good region. I hope Ethereum will going to moon in mid of this year.