Angry Joe at https://www.youtube.com/
user/AngryJoeShow has 1.8 Million subscribers and does review based gaming on his channel of a wide variety of large and well known game titles.
Purge at https://www.youtube.com/
user/PurgeGamers has 328k subscribers, only plays dota 2 and has a couple of how to’s on his channel. Probably not the best person to use, better to use someone in a much more professional circuit.
Cry at https://www.youtube.com/
user/ChaoticMonki – has 1 million subscribers and does let’s plays of a wide variety of games that focus a lot of choice and narrative while giving commentary on it.
VaatiVidya at https://www.youtube.com/
user/VaatiVidya has 330k subscribers and does videos about Dark Souls and Dark Souls Like games.
Totalbiscuit at https://www.youtube.com/
user/TotalHalibut has 1 million subscribers and does a review based channel, his most common one being “WTF is…” series.
Extra Credits at https://www.youtube.com/
user/ExtraCreditz has 413k subscribers and does on video game concepts and creation.
Northernlion at https://www.youtube.com/
user/Northernlion has 480k subscribers and does a lot of indie steam games, with his biggest and longest series playing Binding of Isaac, with a stream of conciousness style commentary.
Super Best Friends Play at https://www.youtube.com/
user/TheSw1tcher has 495k subscribers and is 4 friends who make jokes while playing games, generally bad ones.
Dodger at https://www.youtube.com/
user/PressHeartToContinue has 560k subscribers and seems to do a lot of anime games with a comedic style.
Jesse Cox at https://www.youtube.com/
user/OMFGcata has 748k subscribers and does a wide range of lets plays with comedic commentary
Markiplier at https://www.youtube.com/
user/markiplierGAME– has 5.7 million subscribers and does let’s plays with a comedian style commentary while also adding in highlight videos and extra’s that have to do with his gaming channel.
Pewdiepie at https://www.youtube.com/
user/PewDiePie 34.1 million subscribers and does let’s plays in a comedian style and has extra comedic videos of his gaming.
I recognize that a lot of these have comedic styles, but recognize that the comedy is of different styles. Some do a lot of shouting and generally just playing around(Markiplier, Pewdiepie). Others make joking commentary on what is happening in the game(Dodger, Jesse Cox).