The best Alt coin will be the one that is providing the best value, will be able to actually be used to do real things and one that makes non crypto holders want to get involved in this new frontier.
Security coins I believe are a massive potential too so whoever gets that right will do very well.
We are very young, but we are passionate with real achievements in place already, great plans and big ideas and are very confident our Brix coin will be up there in 2020!