I'm not even remotely the first one to do a list like this, but my recent ponderings about the Netflix shows have got me thinking about the subject, so I figured I might as well share my thoughts here. I've tried to throw out a couple unique choices that aren't on every version of this list, as well as doing a bit of Googling on how the actors feel about the part.
(Warning for straight men not comfortable with their sexuality; I put in some extra effort to find pictures of each actor that show their physicality, since that's a distinctive component of Luke Cage's character. So, there's gonna be a lot of beefcake flying around.)
1) Terry Crews
I've already recorded my thoughts on him (and his own thoughts on playing the character), so I won't rehash that at length here. Suffice it to say, I think he's the absolutely ideal choice for Luke Cage.
2) Idris Elba
I put him on the list because it seems like he's a name that people like to mention for the role, but I personally don't think he's the right fit. There's also the fact that he's already in the MCU, as a great character (who wasn't a great character before Idris Elba started playing him). I'd rather they just expanded Heimdall's role in upcoming Thor movies than co-opted him for another part.
…While we're talking about actors who are already in the MCU, how about this guy? He appeared as Kurse in Thor: the Dark World, but he was buried under prosthetics and/or CGI, so if anyone was gonna pull double-duty in the MCU, he would certainly qualify. As it turns out, he had previously been in discussion with Marvel to play the Black Panther, and I kinda think he'd be a better fit for that role (though I'd prefer Djimon Hounsou).
He has good points in the nerd-recognition factor, having played both Spawn and Bronze Tiger in Arrow, so that might be helpful in drawing an audience. It does seem like his name comes up a lot when people are speculating about who should play the part. He's even acknowledged the fan interest in his taking the role, and said he'd be up for it if it was done right.
He would be one of the lesser-experienced choices of anyone on this list, but I've never had a problem with any of his performances I've seen, and he would certainly follow the proud Marvel tradition of male eye-candy leads.
One thing that's interesting here is that when I was doing my Google image search for these beefcake shots that are making you feel all tingly right now, Isaiah Mustafa was the only one for whom "Luke Cage" was one of the search-refinement suggestions at the top of the page. It turns out he very passionately expressed an interest in playing the part back in 2010, so once word gets out that Marvel is actively casting for the role, he might just start lobbying.
Personally, I'd prefer an actor to a fighter, but at least he has the physicality. I've only seen him in the A-Team remake, and I thought his acting was just okay in that. He was surprisingly lacking in energy or charisma for a guy named "Rampage" filling a Mr. T role.
I'm not a fan of either Transformers or Fast and Furious, so I haven't seen much of his work, but it seems like he's pretty popular, so that's something. He's also been an executive producer on three shows; depending on exactly what level of involvement he had with them, it could be very helpful to have a lead actor who's more familiar with the goings-on behind the camera.
Yes, I admit it, I've seen Hart of Dixie. But he's been in a lot of other shows, too, so even though he doesn't have name recognition, he may have the "hey, I've seen that guy" effect. He's also shown that he can do the more lighthearted bits that I really, desperately hope will be a part of the Netflix shows (as has been the case with the other parts of the MCU).
Williams may not have the geek-recognition factor of someone like Michael Jai White, but it turns out he's a pretty big geek himself, as indicated in this interview, in which he talks about his love for Luke Cage, wearing Captain America t-shirts, and watching Agents of SHIELD every week (and that was even before it improved!).
9) Chad Coleman
I don't watch The Walking Dead, so I don't know about this guy, but he's another one who's specifically expressed an interest in playing this role. In this interview where he talks about how much he wants the role, he even offers his own delivery of Cage's old holiday-themed interjection.
Lance Reddick would be an Honorable Mention for me. I think he's too thin for Cage, but that can always change if he wanted it badly enough. He is tall, though, which is always good for a superhero role. If anyone's wondering why Djimon Hounsou isn't on the list, it's because I really, really want him to play the Black Panther instead. I think he would be just as perfect for that as Terry Crews would be for this.