The next big feature NEM devs are working on is here. 
They have not revealed a lot of details but one of the new features is the ability to create "aggregate transactions" which are sort of like temporary on-chain smart contracts. They posted a screen shot of an example recently: https://twitter.com/2017Lon/status/903291329777504256

ETH does have smart contracts but these aggregate transactions will be MUCH easier and safer to use and are a first of their kind in blockchain tech from my understanding.