Chiming in to promote ink! 
At this moment, the ink! alliance is working on making ink! compile to PVM, allowing ink! smart contracts to be deployed on Polkadot just like Solidity-based contracts.
Once that milestone is achieved, it might be a significant point for the alliance to start considering the Ethereum ABI, enabling both ink! contracts and EVM-compatible contracts not only to run on the same VM but interact with each other. Step by step.
As of today, the following js libraries and utils work nicely with ink! and can be used to build dapps: