Think you two are far overstating Noel's inability to guard on the perimeter. What about the fact that when he plays with Okafor he essentially has to cover for both the post and the wing to account for Jahleel'a suspect defense?
Having to flash to the paint for a quick double team would lead to Noel's man being open on the perimeter. If he was instead playing with someone like Al Horford he'd be much more free to focus on his own assignment knowing that Horford can guard all but the biggest centers 1 on 1.
Nerlens Noel is a special defender from either spot and he's played his best games away from Jahleel Okafor. He could be a dynamic player here and as for the suspect hands, while I don't disagree that they are sub par by NBA standards, he did raise his field goal percentage from 46% to 52% during his second season. Taking smarter shots and learning when best to time his jumps could compensate for his hands, and that's the type of stuff that can hone through game experience.
Noel can get along fine defending 4s, but he's not as good there as he is at center - you said it yourself that his best stretches of basketball have come without Okafor on the court, when he's playing the 5 (and usually next to a big swingman playing the 4, like Covington or Grant). Like I said, he'd be a nice luxury to have and would make the team a bit better next season, but they also have a lesser version of that Horford-Noel pairing already available when you trot Amir out next to Horford.
Just can't abide by the no one's beating Cleveland mindset so why compete? No way do I want my GM sitting on his hands until the Cavs or Warriors begin to face. We need to remain agressive and not fall in love with our players or asset pool. Uniting Smart, Jaylen Brown, Noel and Horford could create an all time defensive lineup, one capable of keeping up with whatever Cleveland could throw at us,
Meanwhile Kyrie Irving reinjures himself with no Delavedova to fill in and Love and LeBron continue to struggle with chemistry. There's no reason to think the finals are 100% out of reach. Did Detroit's management punt down the road during the Chauncey Billups era? I'm sure plenty of people told them no one is beating LA any time soon but they stuck at it. An exception to the rule yes but it could just be the right approach to take.
Nobody in here is saying that Cleveland is unbeatable so why bother, but if you're talking about bringing in a guy as a possible one-year rental you do have to consider how good you're likely to be over the next 10 months. That's the problem with Noel - he gets real expensive next year, especially if he's playing starter's minutes on a playoff team this year, and having over 20 million in cap holds tied up between Noel, Olynyk, and the Brooklyn pick (should they keep it, and if not it will almost certainly be moved for someone making a higher salary), as well as another $25ish million tied up between Amir and Jonas (who would be a lesser priority) gets in the way of that. If he doesn't make you better than Cleveland this year, and there's a chance you let him leave after one season, that tempers his value to you in trade a bit, particularly when you're talking about moving good rotation pieces like Avery and Smart who stay cheap for an additional season.
Is there a Noel deal that makes sense for Boston? Yea there is, and he'd add a nice dynamic to the team, but flipping one of the teams' cheap all-defense-level perimeter guys (even though Avery and Jae got all the votes, I suspect Marcus might be the best defender of the lot) isn't it.
I don't want to get rid of Smart and Noel makes so much sense here I honstly wasn't even considering the potential that he'd be a rental. FWIW I don't think they want Smart either, too much of a potental leadership turnover. We're in a position for Smart to rise as one of the leaders in this team. Doubt Philly would want to mess with Ben Simmons... Which is why I could see them being interested in Jaylen Brown.
I love the kid and, if it's what the FO wants, I hope he retires a Celtic. But if I'm the 6'ers, Brown's my real target. That team is about too infuse an unprecedented amount of talent onto the floor. Egos will be tested and it will take dynamic personalities to rise up. Could imagine Smart ruffling feathers but Brown potentially fitting in just right. They have a need at Jaylen's position and his open court athleticism would be exactly what Simmons would need as a fast break running mate. Add on to that his dynamic personality and he could become a Philly legend.
As for the Noel rental, ignoring the home town connection factor, the obvious fit, and the fact that we'd be able to offer him a 5th year, I'd also imagine that his market might be dryer than you'd think from a former top prospect. During the draft process he fell as much for his strange prickly nature as he did for his uncertain health. There were rumblings around pre draft times that teams were unable to contact him, they'd be told to call a number and no one would ever answer. Kind of seems like a bit of a difficult guy to have in your locker room, especially if it's not strong.
We don't lack for leadership here and we can just tell Noel to play his game. You say Noel and Horford overlap in their skill set but then Stevens has also said many times that 4s and 5s have largely interchangible responsibilities in his system. Noel has made strides toward shooting the mid range J and IMO would coexesit with Horford. Don't twist my words when I said Noel had issues playing with a Center like Okafor was not saying that He can't play with Centers. In our aystem, playing off Horford, Noel could be a defensive big man, not just a defensive 4 or 5.