I think that the cheating rules are fine as is. 2 year ban if you're caught cheating first time, perma after that. I'm not a 6s player so I don't have to play against elijah, but at least in the highlander scene i think there are actually more current invite players that were banned for cheating that are still playing and not cheating, than there are players that were banned for cheating, made it to a high level, and banned again for cheating.
For example, the best HL scout right now, blank, was banned for cheating in his second season, and after getting unbanned made it to invite in two seasons. Nyxi was banned in his first season in Platinum, and after coming back he's been a mainstay in invite. eX.Hunter was banned for cheating in Platinum, unbanned and same thing as nyxi. Hyphen same thing. Not an insignificant portion of the top highlander players.
There are just too many players that I can think of that have been banned for cheating and reformed themselves for me to be behind 1 strike and you're out forever policy. Specifically for elijah (who is what this whole thread is about) demo request him every game and if he's cheating still, he'll be gone forever and you'll get your precious match points back. You don't have to scrim him. AC admins should have reviewing his demos (and other freshly unbanned cheaters) at #1 priority, over every other demo requested.
Elijah is an edge case. There are plenty of good players that have been banned for cheating in the past, and came back as a significant contributor to the competitive scene. I'd rather one match in two years be a loss than a few kids in their teens lose their opportunity to come back as adults.