Hello Dayn Brian!
What I am about to say is just my opinion and from what I have learned. I don't have a gaming channel, mine is about traveling but I thing I can give a few ideas.
About the INTRO, when we talk about a 30 seconds intro it sounds short and normal but in reality its a very long intro, in the long run imagine a subscriber of yours every time he wants to see a video of yours have to watch first a 30 seconds video, the 5 seconds adds are already long imagine 30 seconds... I thing a 5 to 10 seconds is a perfect timing for intros, just letting people know that this video was made by YOU! This is your brand!
COMMENTATING on your video is good because you add a bit of your personality to the game, I usually even advise to record yourself with a camera and put it on the bottom left corner so people can see you. The diference between your channel and others is you, you can have 1000 people making the same videos about the same game the only thing that will make someone choose your video is because of you, so give a bit of your personality to the channel, people will get attached to it.
About the OUTRO, after you finish your game play, and while still playing you gave give your "good bye's" and shoot out for liking and subscribing because you want them to be entertained while listening to you otherwise they will think: "Oh, this guy just finished, there is nothing else to watch lets check another video". You wanna keep them "busy" on your video. You want to maximize the viewing length of everyone cause that's nowadays what makes your videos go up in the YouTube page.
I hope I could give you some ideas, again, this is just knowledge I have been learning and might not apply for all the channels or videos.
Good luck on your channel
