If it was just me, I'd go a simple route. Simple is often underused and underrated because, for some strange reason, some fans believe that everything is supposed to be this epic happening or it flat out sucks.
When Kofi makes his return, I'd book him to come out to do a promo without any music, without wearing his ring gear and with a different hairstyle. He's not going about all happy and smiling or slapping the hands of fans but walks confidently to the ring. I wouldn't want to turn him into some stereotypical black thug, so I wouldn't have him dress like one or come out to the predictable gangsta rap stuff. I'd have him dressed in a simple pair of black jeans and a solid black t-shirt.
He picks up the mic after getting into the ring and begins to address the fans rather than Ryback, saying he'll get his payback on that "Neanderthal lookin' bastard" soon enough. He says that he has a bone to pick with the fans. As he goes along, more and more conviction comes into his voice as he describes his beating at the hands of Ryback, with clips being show on the big screen. During his promo, he addresses the reaction of the crowd as Ryback plowed through him, namely chanting "one more time" as Ryback put him through table after table. Kofi talks about how hard he's worked in WWE and how many times he's put himself on the line, to give them their money's worth, yet they react to him getting beaten down like a dog with glee, encouraging Ryback to try to end his career with his wife and newborn son watching at home. They cheer as he's nearly broken in half and has to be half carried back to the locker room, etc. He discusses the surgery that he had to have due to what happened and put him on the shelf. During his recovery, he has time to think back on his career, especially attacks he's suffered and beatings he's endured, often with people cheering on the beating as it went down. He came to realize that he's nothing to the people he's killed himself for all these years, that he was just some happy smiling guy they could wipe their feet on. He could say something along the lines of maybe "here's what I think of you" as he pulls of his shirt, wipes his ass with it and then tosses it out onto someone at ringside.
Before he's about to leave, he's interrupted by a wrestler, I'd probably pick Chris Jericho, who comes out to talk to Kofi. He tries to console Kofi by telling him he understands he's angry and he's been in spots where he's also believed that people have just turned on him or didn't give a crap. If I'm not mistaken, this is the biggest injury Kofi has had since he's been wrestling, so maybe Jericho could mention that and explain that dwelling on such injuries, as one recovers, can play all kinds of tricks with your head. He knows because he's been there himself. At this time, Kofi is sort of hanging his head a bit and runs his hand over his face like he's realized he just said something awful out of anger. He shakes Jericho's hand briefly and pulls him into position to deliver the SOS, which he does. He then starts to pound Jericho with punches, kicks, stomps, etc. whatever springs to mind. As Jericho is stunned, Kofi pulls him to his feet long enough to deliver Trouble in Paradise and stands over him briefly before climbing out of the ring. As he's about to leave, he stops and gets this look on his face as if he's just had an idea. So he heads back and pulls a table out from under the ring and sets it up inside. He pounds on Jericho a bit more, maybe even running off a couple of refs as they've come out to lend some aid. He puts Jericho on the table and climbs to the top to do a kind of modified Boom Drop, which is basically just a double leg drop, and puts Jericho through the table. Kofi stands up and is fired up and looks out at the crowd and asks them "one more time" several times in an attempt to get the crowd to chant it back. If the crowd chants back, which I have a feeling they would, Kofi could give them a rude gesture in response, not the middle finger, but one where he sort of pumps his right fist upward while putting his right hand in the crook of his arm, which I think means to "shove it" or "go to hell" or something along those lines. He smirks arrogantly and strolls casually out of the ring and back through the curtain. This also sets up a good feud & series of matches with Chris Jericho, who's excellent at putting over others while still looking like a champ himself.
I wouldn't have Kofi dwell on hating on the crowd for turning on him too much, but would have him move on, in subsequent promos, into deeper detail about how he came to realize how much of a chump he's allowed himself to be in WWE, how he's allowed himself to be just another body on the roster, how the birth of his son caused him to start reevaluating his career and how much bigger & better he wants to be so that his son can really be proud of his old man, etc. The fans "turning" on him was sort of the lynch pin that convinced him to truly "take charge" of himself and where he's going.
Anyhow, that's pretty much how I'd do it if I were booking the thing.
