Right now you need to play for 30 minutes on 7 days (they don't have to be consecutive), play 4 games you haven't played before (for at least 2 minutes) and unlock 6 achievements. These seem like obtainable goals and all stuff that should happen naturally through regular play.
People will definitely try to create bunch of AFK farm games with names like:
AFK Skin farm 30 minutes (1)
AFK Skin farm 30 minutes (2)
.....
AFK Skin farm 30 minutes (127)
And with achievements that will pop after each 5 minutes of playtime
I understand the motivation behind it, but its really easy to abuse and might replace AI slop games with AFK Farm games.
4 Games per week could be a big motivator for that i would decreased it to 1.