I think it would be extremely interesting if we could represent at least one metric in the performance manage dashboard, for personal analysis.

For instance, in my case I want to display HRV -in fact I enter the 10 day rolling average value of HRV, that I obtain from another system- against the already visible CTL, Fatigue, Form, TSS... I have found trends in HRV (the 10 day RA) to be of great significance when gauging if your body is being able or not to cope with the energy demands of training and life in general.

For example, I was following a training regime where theoretically my CTL increased, while keeping fatigue and form more or less under control. If the adaptation had been positive, I would have expected an increase in HRV trends; but in fact it was plumbing slowly but steadily, because I am also following a keto diet, so I understood that training load was excessive in that context and had to step back, to avoid overtraining. Soon after that I've seen my HRV numbers increase, while keeping CTL and form stable, and seeing progress with my keto diet.

A proper HRV value for instance can be used to account for a lot of the things going on in your body (and life: stress, illness, diets, etc...) and that will affect fatigue, recovery, training capacity and thus form.

In general, I think that being able to cross-examine metrics against performance parameters is extremely interesting (with the necessary understanding that obviously there isn't always a correlation).