IMO Okafor isn't the answer, first he's an old fashion back to the basket center, that doesn't fit into the style of play CBS and DA want to play. As an organization you must settle on a style of play that your team will be designed around. You can't be every style.
Okafor is a walking "minus" because of his "swiss cheese" defense. He struggles to get back on defense, his conditioning is suspect. He doesn't rebound very well. IMO I feel Okafor will slow the Celtic pace down to a crawl.
Noel runs the floor well, can defend 3 positions, he adds energy to the game on both ends, his playing pace is much faster than Okafor, he protects the rim, and is an improving offensive player. He's far from perfect, he'll never be a Cousins, but he's a better choice than Jah.
Secondly, we need a wing that can consistently score, add energy, and find his own shot on the second unit. Kind on like what Green has been doing for several games now.