Came to take a peak in this forum to see what's new to find someone desiring for measuring tools, something I would also love to chime in on.
1) Survival:
*- Flag Marker: One flag to the next would give you the number you're seeking. The number could pop up on the flag, or it could pop up when you look at the flag in the place of the ID number of items on bottom left.
*- Cones: Similar to the above, if in a decoration sense. Same function, yet different appearance.
2) Creative:
Similar (or a mesh) of both the flag & the distance ID in the player tab menu type thing.
Then you could have measuring tapes, digital devices, & etc. Whatever can be managed to be added in. Some for short distances, some for longer distances.