Maybe the golden middle path is compressed risc instructions. E.g the risc-v C extension, where the most commonly used instructions take 16 bits, and the full 32-bit instructions are still available. Density is apparently slightly better than x86-64, while being easier to decode.

(yes, I'm aware there's no high performance risc-v core available (yet) comparable to x86-64 or power, or even the higher end arm ones)