Why not, for the 10th anniversary of LOL, make a "Classic Skin" Map?
What I mean is make a map skin for SR that brings it back (For the most part) to the look it had PRE-VISUAL UPDATE.
This old thing from pre-2014.
https://scdn.slashgear.com/wp-content/uploads/2014/06/Summoners_rift_season_4_map-820x420.jpg
It can bring back memories, and/or give players who started AFTER the VU that Summoner's Rift got the chance to see what it looked like back in the day. Like the others you've done, such as Snowdown/Winter, I wouldn't say it has to be permanent, perhaps just lasting the duration of any events you might hold for the 10th anniversary. You could include an option to opt out if players prefer the current look, like you do with turning off any Map Accents/Alterations like you have with Star Guardian, Arcade, Odyssey and so on.
I don't know, just throwing it out there.