I don't know if a COO would work at Tesla. Tesla has had strong lieutenants before, and they were fired. Shotwell at SpaceX may be a unique case, don't know her personality and what she actually does.
Given Elon's penchant for making outrageous production and sales predictions, I don't know if any QUALITY person is going to want that COO job. This is a company that has no problem delivering products with known manufacturing defects in them (Early Roadster, Model S and Model X quality issues, that's 3 for 3 guys). And Elon definitely got out way over his skis on Tesla Energy. Powerwall v1 was a complete failure, v2 is still to be shipped.
I will grant you that Model 3 is a game changer. Can they sell it as a profit for $35K? Well, Elon says they can.
This is a very tumultuous time for Tesla. We all knew that at some point in time, Model S sales were going to flatten out. If was originally supposed to occur at 20,000 Model S per year, and obviously demand has been much more robust than those early estimates. But we now seem to have found the market limit for Model S, maybe, or maybe Tesla has finally grown to the point that sales cycles affect it (anyone know if Q2 is slow in general in the auto sector?).
And now Model X demand seems to be down as well. A friend of mine was given a 2.5 month time frame for delivery of a new Model X last week.
And in the midst of this, interesting time, for Tesla, Elon decides that now is a good time to use 100% of his executive's time for the Solarcity due diligence (I'm sure his CFO is thrilled right now, Deepak got out just in time, hmmm).
That's either amateur hour on Elon's part or he thinks he needs to do it to head off a train wreck. Neither is reassuring.
Yes indeed, some "weak investors" got out with the SCTY acquisition news. But not all the big funds have moved out. Elon is going to be testing their patience.