I'll take the (1) (2) (3) thingy as option 1, option 2, and option 3. So,

I agree for the choosen mods, day 1 is OK.

For the day 10, I think the option 2 is going to be better if you change it to <1000, rotating those mods is a nice plan, I guess, so people won't get bored easily because of playing in the same mod again and again. It's also a little bit more challanging.

As for the Day 20, the option 3 is good if you change it to <500. Because it's not like every high ranked players are always active, some was only just obtaining the rank, and when they got the rank, they just exit the game and waited to get a new higher rank opponent to beat or even just stay on spectating until that higher rank opponent appeared.