RE: NEM into the top 5 cryptocurrencies
The first thing that attracted me to NEM was the proof of importance concept. I really dislike the fact that Bitcoin and Ethereum mining costs a huge and ever-increasing amount of electricity - NEM does away with miners and instead has individuals that are important to the network "harvest" a small amount of XEM by verifying transactions to the block chain. Proof of importance involves more than just holding a certain amount of XEM - it also takes into account length of time active in the network and transaction history in determining importance. Here is a good place to start reading about proof of importance.
There are other cool features - super nodes for one, but there are other alt coins who use this concept. Also supporting on-chain multi-sig smart contracts in basically a point and click manner gives it a HUGE leg up on Ethereum (which supports this but developers have to write their own smart contract which is quite complicated and easily messed up, leading to potential security vulnerabilities).
The other reason I am high on NEM besides what I consider to be some clear technological innovations that give it more value than Bitcoin or Ethereum, is that it is still relatively under the radar in the west. There is a big ($40 million) marketing campaign planned for this year after the release of Catapult (major code upgrade introducing new features and migrating NEM to C++ from Java). I don't think NEM is going to be under anyone's radar in a few months, so that is why I think the time to buy is now.
thats a great answer, thanks for taking the time!