At the heart of Ethereum is the EVM, the engine powering the entire Ethereum network. It is the runtime execution environment for smart contracts and blockchain. There are quite a few lower-level protocol improvements proposed, including some at EVM opcode level. There are many discussions about improving the account model, including further account data abstraction.
You can check out the Ethereum EIP site for more details (https://github.com/ethereum/EIPs/issues).
One of the interesting topics worth discussing further is the next generation of the EVM, eWASM. It is an Ethereum version of WebAssembly (WASM).
WebAssembly is a W3C standard, defining the binary instruction set for a stack-based virtual machine. It is intended for compilation of C/C++/Rust and similar high-level programming languages and for deployment on the...