What if they populated the ranked list with some AIs?

“sooner or later” it would take a loooong time to significantly change the average elo: Effects of changing the starting elo to 500

TL;DR: with 500 starting elo, adding 10 000 new players only shifts the average by 100 points. I reckon 10 000 new players takes several years

then players between 600 and 900 elo will be fighting bots a lot. You don’t queue up for ranked to fight a bot

I think this could be the solution: put a bot of each difficulty level (standard, medium, hard, extreme) on the ladder to find out what elo they have. then if a new player wants to join they can self-assess (or maybe even make them play against bots) which level they can/can’t beat and make put their initial rating at the level of the corresponding bot