An impactful wing will come more from a Mitchell trade (or Garland, but screw trading him) than it will Allen.
The teams with whom you could get trades (Phoenix, but lol doing that with their new owner -- Dallas, etc) that actually would be interested don't employ those kind of wings now. The Cavs absolutely needed to score one in the draft when they were tanking and they rolled snake eyes.
I really need the "Spacing Uber Alles" crew who (IMO, are overreacting to one playoff series) to think hard about this -- it's not happening unless either the Cavs find themselves in the middle of another team's desperation to find a superstar (like they did when they acquired Allen) or a team forced to cut beat because of the new CBA or they're blowing things up (how they got Mitchell). It's not going to come today from an Allen trade unless it's one of those two scenarios. Maybe a distant third is a sign & trade involving LeVert to a team who is lacking in ball handling.
Find a real #3 big (Eubanks, Saric perhaps) and two buy-low forwards, one of whom possibly getting MLE dollars.
Acquiring Keita Bates Diop and waiving Windler (whose salary is not guaranteed) is an easy step forward.
Target guys like Yuta Watanabe and others with the other exceptions the Cavs have.
Might have to actually use that GSW 2nd rounder with a fence-swinger that is exclusively the BFA (best forward available).
Those moves at least mitigate the non-JBB issues with the team.
The ones who really need to be replaced before Allen does are Cedi, Wade, Windler. One is not available, and the other two do not provide enough shooting.
Cedi and Wade might be worse value than Allen now, but they are more of a drag than Allen is and will be on this team post-Lauri and Love.