I'm sorry to say I burned out on it in late November and haven't made progress since.
That said, I'm probably going to throw out most of what I have and take another stab at it soon. On the bright side, SharedArrayBuffer has inched forward since then, so I'll be aiming to incorporate that. Not planning to include it before was honestly demoralizing.
Suffice it to say, don't wait on me for anything at this point. I've kind of consigned myself to left field.