I didn't know it stopped and gave you a total score after a while. I figured it just kept going, and got bored at "gargantuan". At that point my scores ware bimodel - either 100 or 80 depending on whether the font agreed with my spacing next to the leading capital letter.

Never done any font design. Initially I was getting 70s, but after playing it a few times over the last few weeks I think I've gotten the hang of it. Mid 90s on average now.

Personally, I got 90/100, I also have experience with TeX and I've designed a few fonts

93/100 here, wonder if there’s a difference between mobile and desktop? I played on mobile and being able to bring my phone right up close to my eyes seemed to make it easier to judge the spacing than if I’d done it at my desk.

95, using a phone and the old trick of squinting a bit to get a sense of the overall layout.

where can I display my average? (I got 100/100 on all but one time)

How much fonts did you play?