ARAMs random generator is broken.
I have 35 champs available to me. I played 6 ARAM games today. 3 times, Sejuani came up. Including 2 games in a row. I was sick of playing her so I rerolled for Poppy on the last time.
Seeing her 2 games in a row is a 1 in 1225 chance. Now I'm not a statistician but seeing her as the result 3 times in 6 games is rather improbable.
Now, poppy is interesting for the reroll, because I tend to get her a lot as well. I was happy for the break, but objectively she's a champ I'm seeing too often.
It's bad enough I can't narrow the pool down, but for it to be streaky is worse. Especially when I never get to start a game with the champs I want to play. If you are going to keep it so that certain champs come up more often for certain people, then at least make it so we have some way to weight champs in our favor.