Nimiq just released their main net, and there product is quite good!
Considering that they developed their own blockchain in high quality ES6 code, and that JSECoin is made to be embedded on a website, I guess switching from Ethereum to Nimiq would be more than appropriate.
The reason we are using Ethereum is because their ERC20 contract has become an industry standard. The vast majority of the blockchain industry uses it which means by making our technology work with ERC20 it opens up all the options for 3rd party wallets, exchange integration, hardware wallets etc.
None of this would be available if we used Nimiq, EOS, Lisk etc. instead.