Its a little too ridiculous to actually happen but it would be interesting. It would be Thompson's 4th year and Waiter's 3rd along with any draft picks they get from now in their second year. That would be a hell of a talented team for sure regardless if Varejao performs at the same level or not. Adding Lebron to that team would make them easilly a title contender for sure.
LeBron is just an evil genius! The team couldn't get young talent (or talent really at all) to help him when he was in Cleveland originally. After he was drafted, his impact on the team was too great, and unlike a Seattle/OKC situation where they could amass multiple top 3 picks, Cleveland couldn't do anything in subsequent drafts. They drafted 10th the year after and busted with Luke Jackson. They didn't have picks in 2005. They never were able to bring in young guys via the draft to help him.
So, how do you finally get that?! You leave knowing that they'll become one of the absolute worst teams in the league for a while, and then come back after they've cashed in on those draft picks! It's genius really!