@peppy pinging to gauge if we even want this before I even consider review

I'd like to leave an idle comment why some people might want this, but it's mostly from my own perspective, feel free to ignore/nuke.

Since we have an automatic offset adjustment anyway and we don't have to pay attention to the hit error, sometimes I like being able to take a peek at a very specific part of the map, if I was unstable during x or y or just see what happened but with actual timing values, not only where the hit events landed on the graph.

Yes, the visual representation is enough to tell you if you are doing bad just by reaching green section or if your play is all over the place, but on high accuracy settings I assume you'd want to see those numbers as low as possible, even if scattered.

It might sound silly, but some people just like numbers. Might be a personal preference, replay analysis, live preview when livestreaming, and so on. I do that with other components on osu!taiko too, e.g. splitting HitError/UR into Rim/Centre, having 6 of them on screen, as silly/useless as it sounds for others.

I think this is a cool feature to have. Although I may have placed it below the existing "arrow" as a toggle for more information, rather than replacing the arrow (but i don't feel too strongly about this, so up-to-the-reviewer).

placed it below the existing "arrow"

I attempted a mockup of this and personally I'm not a fan, since it requires you to move the element further up into the playfield to fit 'nicely', and making the font smaller makes it too hard to read at a glance.

Let's not ignore that the reason it's hard to read is that the sizing is all wrong. The number is way too small and the arrow is way too big for it to work.