The designs of each rune and how they interact with the secondary trees etc really show a lot of love. Each one seems to correlate to a faction in Runeterra which I found really interesting. Is there any more solid lore behind them and how they relate (in their current form) to the Runewars?
World Runes, they are World Runes.
First and foremost runes for the game have no true connection to the Runes from the lore, although they are inspired by it.
Anyway if you want Rune Wars lore, sadly there is very little beyond references to them scattered here and there. The only detailed story we have is through Ryze's lore (you can check that out if not already), which describes them as capable of decimating entire landscapes.
Otherwise nah, nothing too solid for now.
