You are right and wrong. The weight distribution is the source of the problem. Lotus did the best they could do with the technology and engineering available at the time. They also had to meet the price point so they had to stay in budget using as many off-the-shelf parts as possible and also save on tooling and production costs. What we have is the best compromise they could achieve while minimizing all of the bad effects. Pretty good for a 1st gen production car. I am sure it would have gotten better and better. For instance there is no rear sway bar. The car was not meant to be a track car but it really isn't a sports car either. Anyway, the design of the suspension is very dependent on the size of the tires with no brake proportioning and no ABS or traction control to mitigate the bad characteristics of the car. On new cars with drive-by-wire, you can tailor the feel and the control effects so you can't get yourself into trouble. They couldn't do that in 1980.