I'm going to throw a name out there that I think is more realistic now than it was at the beginning of the season, and also because it seems more realistic than some of the other options being thrown around: Devin Booker.
Booker is on the record now saying he's not missing the playoffs again next year. Well, I have to think the Suns aren't delusional enough to think they'll make the playoffs barring some crazy moves. I also can't imagine Booker has built up enough clout with that fan base that they'll revolt if they trade him. He's due for a big extension, and the Suns may feel that it's simply not worth it. The Cavs could send Phoenix the 8th pick and Rodney Hood as a cheaper replacement. The Suns would have two top-10 picks, Jackson, Warren, Hood, Bender. They could potentially grab Ayton and Young. Ayton, Young, Jackson, Warren, Hood is a pretty good starting 5 for a young team.
Why would the Cavs do it? Well, Booker has proven to be a very good scorer on and off the ball. He has drastically improved his playmaking chops (go look at his 3rd year numbers compared to Kyrie, and they compare super favorably). He's also a knockdown shooter. He's not a great defender, but that hasn't really stopped them before. He's also only 21 years old, which a pretty serious injection of youth on a team that sorely needs it.