I spent some time and effort and tried to look through a ton of reticles under different conditions durign the course of the last year.
I am not hugely picky since I am quite comfortable with floating dots, floating crosshairs, etc but I think the drive to ever smaller primary aiming point is not the way to go. I am not hindered by a slightly larger aiming feature because I was originally trained to dissect the target and I can aim with the edge. Now, too large is not good, but there are very few reticles out there that are too large. Too small makes a much bigger problem for me although illumination helps with that under low light conditions.
In practical terms for floating dot reticles, I want something in the 0.05 to 0.1 range. Smaller than 0.05 is too small for me and if you want to go that thin, I prefer a crosshair or something along those lines to a dot. In general, I have designed a few reticles for a few different people and I prefer a three line thickness design guideline where I can make the tree thinner than the primary aiming point. Primary aiming features have to be designed in such a way that they are useful across the entire magnificaiton range, while the tree is only used at mid/high magnification.
TT's 0.075 mrad is perfectly reasonable for me.
ILya