Right now elemental types do not seem to play ANY part in the match making. If they did, maybe it could help balance things out more? So if I have a 5k advantage I would face a team that at least has a heavy elemental advantage over me.
As for the AI playing better, I see no issue there. I am not talking massive differences. For a 5k point disparity, maybe the person with a lower power rating would have all their AI make 5-10% more shots? Something relatively minor, but enough to still help lower the gap
EDIT: And for those saying an 8-10% gap “isn’t that big of deal”, it is when it’s clearly the difference between a loss and win most times: