LeVert is playing great defense - the Cavs are 8.9 points better defensively when he's on the floor. His offense has been neutral at +0.5.
I don't think LeVert can continue to hit 44% from deep. But he won't continue to shoot 27% on mid-range shots, either. He's playing a new position offensively and they're moving him around. Sometimes he's with Mitch and Garland as a small forward, other times he's a guard and Cedi or Wade is at small forward. He's still getting to his spots and taking high percentage shots - he's just missing them.
Even if his 3-point percentage drops off I think his offense will improve as he gets more comfortable with his role and the mid-range 2's start falling. He's only shooting 40% at the rim - 20% lower than his career average of about 60%. His short mid-range shot (4-14 feet) is down from 44% last year to 29%. Those numbers will surely increase. His assist to usage percentage is in the 90th percentile among wings.
He's doing very well defensively, dishing out assists, and on 3-point shots. He's struggling with the short mid-range shots and at the rim, but those numbers should ReVert to the norm. If and when that happens he'll be one heck of a player and a very versatile one at that.