The reason I lean further towards moving on from Pickens than you is I regard Pickens as more of a DJ type, and maybe more so than DJ himself. That Dallas game where Fields threw one final pass to where Pickens should have been but wasn't because he didn't run full out on his route really sticks with me, particularly as it came after a lot of grumbling about his route running effort and accuracy from the QB School in the Fields era.
There's other low effort - or in some cases low IQ or reliability - plays that really stick with me too. Failing to get both feet in bounds on a touchdown last season. That jump to the sidelines this season. Getting taken out of some plays very easily vs the Browns. His drops are way up this season too, and some of them have been critical. If that whole worry about the "if that guy isn't giving his all, why am I" gets played out, then I think it does with George. Particularly with the accusations about him not showing up to meetings on time.
On the other side though, your point about this being a short window is also true. I can buy gambling on him behaving himself well enough through the window because otherwise they don't have a WR1 and that's a worse gamble. That said, by the numbers, I'm not sure he's in the top 10 WRs in football right now, and I'm not sure that's going to change unless he gets a lot more dialed in on his details.