I would also add Angry Joe to the list. Lindsay survived because she rebranded herself as a breadtuber, but Joe is the only ex-Channel Awesome person still going strong, doing his Angry Reviews and standing on his own without Doug. He might even rival Doug in views. He's probably the only real success story I can think of from that group.
Don't get me wrong, Joe has his own questionable stuff, and I'm not really a fan myself, but credit where credit's due, his niche is actually fairly important (videogames), unlike the other Doug clones reviewing niches nobody cares about, like 70s movies? And unlike Lewis, he's evolved with the times and even expanded to reviewing nerd media in general.