My first reaction was “no”...... because if I have the #2 pick, I expect to end up with a guy with All-Star potential, either by using the pick on a high-ceiling guy, or by getting one in return. And none of Dinwiddie, Allen, or the #19 really fits that.
But I’d probably do this deal anyways. Allen was just 21 last year, and his advanced stats are excellent (better than Dinwiddie’s). Next year we’d have a great roster, though Dinwiddie has a player option in the summer of ‘21 and would probably leave for more money somewhere else. But we’d be able to retain Allen (he’ll be an RFA in ‘21). And I think there’s really good depth in the draft - guys like Bane, Saddiq Bey, Poku, even Tyler Terry would be really interesting at #19.
The thing we’d need to try to shore up is outside shooting - would need to get at least 1 or 2 more marksmen, or the only “good” shooters on the team are Curry and Klay, so things could get clogged. But I think I’d do this deal.