The Rune Stats display is in a really inaccessible and awkward position in its current state. It doesn't fit very well in the box that contains it and in order to view it, you have to toggle off your champ stats display or hit C. There's no at-a-glance option to view both.
I feel like Riot really missed an opportunity here to make good use of the top left corner of the screen, which is currently completely unused.
I think it'd be a great spot to put the new runes stats display. You wouldn't need to take up much space; in fact, you could do it in less space than the current display window occupies.
I made a template to demonstrate my idea in the image below:
This will have the following attributes that the current rune stats window doesn't have:
1. Take up over 20% less space
2. Be mostly transparent except where it's closest to the screen
3. Match the League of Legends aesthetic
4. Be clearly and stylishly visible at a glance
5. Be clear and easy-to-read
6. Be uniform in scale
8. Be in a different location from the Champion stats display, leaving the player able to view both at a glance
I really hope Riot considers this idea. I really like it and could very much see it becoming a part of League of Legends. It fits very naturally on the screen and I hope you'll agree with me.
Here's a clean version for reference:
You can see it looks very clean, takes up almost no space, and the champ stats window is still open and visible.