Reinertsen's books are very, very good. The most recent and most up-to-date is Principles of Product Development Flow, which that chart came from. The previous one, Managing the Design Factory, is pretty similar and I think it's a better read.
Another great takeaway from it is to prioritize things by cost of delay, or even better, what he calls Weighted Shortest Job First, where you divide the cost of delay by the expected length of the task. The only problem is that the same people that want to get oddly formal and inappropriately rigorous with things like story points will want to turn cost-of-delay into an accounting exercise - or object that it's impossible because they don't have the accounting system for it - which misses the point entirely.
That is very true. I'm going to write something up about WSJF in practice in the future, but it has some real benefits to fixing that issue.
Particularly when you get the decision makers in a room and get them all to agree on the estimated value of each item. Not only does it remove the numerous priority #1's, it also gets everybody aligned on what the real priority #1 is and why.
I've seen it done where people are surveyed separately and it only works well when the people involved are forced to have a conversation to put real numbers to their assumptions, coming out with agreement. The other side effect is that it solves the squeaky wheel problem.
Another great takeaway from it is to prioritize things by cost of delay, or even better, what he calls Weighted Shortest Job First, where you divide the cost of delay by the expected length of the task. The only problem is that the same people that want to get oddly formal and inappropriately rigorous with things like story points will want to turn cost-of-delay into an accounting exercise - or object that it's impossible because they don't have the accounting system for it - which misses the point entirely.