A couple of thoughts of mine; perhaps some are already on the list, perhaps not, but anyway here goes. "Wouldn't it be nices", low priority!
I'm obviously a novice and can't remember everything easily at my age. There's a lot to know. What would really help a user like me - especially as the axes mean different things on different graphs - would be some tooltips on the graph's axis numbers to remind me what they represent. Even if it's just which direction (towards top of X axis vs towards bottom of X axis) means "too dark" and which means "too bright".
Also tooltips on the titles (at the top-left corner of each graph) would help me. I do know that these things are already detailed in the manual in a much more comprehensive form, but rather than to have to refer to it there's an opportunity to add in the summaries I think. Eg the white title text of the Dif EOTF graph could have a tooltip giving the summary eg "The Dif EOTF graph shows the difference in the measured EOFT from the target colour space EOTF, with the 0.0 graph line representing the selected target colour space EOTf, be that power law 2.4, BT1886, HLG, ST2084, etc.". That would help me remember that the Y axis units on that graph are 1/10th of a ???? and the negative values mean a point above the X axis, ie a red negative number, means "darker than it should be".
NB: I am, of course, very conscious that a base level of knowledge is required to do anything, and would never seek to dumb things down to an excessive level. But this wouldn't be "in your face" Fisher-price stuff I don't think, just a friendly tooltip for newbies and people with bad memories, and it may even reduce support work!
Now the bigger thing to ask. I remember a discussion about the final point of "Diff EOTF" graph and the fact that it's extrapolated. I had forgotten this, and in this post I have no particular side to take in that discussion! Nevertheless because I forgot about it being a special case, I was discombobulated when reading the graph earlier today. What would really help me not forget in future, would be if the lines between the penultimate point and the final point - the extrapolated portion - were dotted instead of solid. That still keeps the graph from looking as if the final point is missing, but is also a nice reminder that the final point is extrapolated. Would that be possible please?
I've done a mockup diagram in case I haven't explained what I mean very clearly. Thanks!