If you haven't already done so you may like to read, "Slide Rule" by Neville. S. Norway. One of the design team for the R.100 (the one that worked) and founder of Airspeed, especially his summary and brief analysis of his exit from Airspeed and why his departure was a good thing. The book highlights that the major challenges of running projects haven't changed much in the last 100 years, i.e. they're still mostly about people & "politics" and the engineering problems are nearly always the least of your worries.