Piggybacking on this comment to say, I bet a lot of people's first question will be, why aren't you contributing to Octave instead of starting a new project? After reading this declaration of the RunMat vision, the first thing I did was ctrl-f Octave to make sure I hadn't missed it.
Honest question, Octave is an old project that never gained as much traction as Julia or NumPy, so I'm sure it has problems, and I wouldn't be surprised if you have excellent reasons for starting fresh. I'm just curious to hear what they are, and I suspect you'll save yourself some time fielding the same question over and over if you add a few sentences about it. I did find [1] on the site, and read it, but I'm still not clear on if you considered e.g. adding a JIT to Octave.