I think bitcoin and eth will do their best to make it to the top since they thought that litecoin can't make it to top. They will do their part to get that spot and the competition will be more aggressive and more serious.
As it stands now, litecoin may not be number one in the near future over bitcoin nor ETH, firstly,
Litecoin is built to complement bitcoin grey areas and i think it may be very difficult to for litecoin to be number one.
Again, Bitcoin and Litecoin are often compared to gold and silver. However, I think they’re more like Coke and Diet Coke. Some people love Coke, others want that great Coke taste but with less sugar. Coke and Diet Coke are on supermarket shelves all around the world. They are right next to each other and they probably always will be.
Now for ETH, it obvious that it uses a different block from bitcoin and litecoin, and i think that it may be possible for litecoin to take number two position based on it similarities with bitcoin ecosystem. Remember that ETH has become popular and many other projects are built on ETH blockchain. This competition goes on and we keep watching how everything play out.