I'll try my best to help out
Channel art this includes banner, logo, and thumbnails. Your logo is alright if anything I would suggest making an icon rather than text but its completely up to you. Your banner could use some improvement while yes it does show you are a gamer its rather bland and doesn't really draw attention, I suggest looking around for someone to make a banner for you. Thumbnails are also something you should work on Creeper World 3 thumbnails are alright but the others fail to grab attention they look boring and when placed up next to other more interesting backgrounds they don't stack up.
Video quality this will include how the videos look mainly. You have HD quality content which is good so not much to say here
Audio and commentary this part is probably where you need the most work now having watched a few videos I see that for one you say umm and uhh way to much its fine to say them once in a while or if you make a mistake but you say it extremely frequently so that is a must to work on. Another thing is you've got to sort the audio problem out I've heard you make a note of it but to be honest it degrades the content severely and it really needs to be addressed. Now the final thing that marks your channel is the commentary itself or lack of it sometimes but you need to talk 13 plus minutes of no commentary is very hard to watch for many people. If you count that with the thousands of gaming channels out there you need to stand out and when I say this I don't mean to offend but there is nothing that stands out.
Now I say this because a lot of the games you pick to play are kinda obscure or irrelevant at this time, serving a niche is fine but you have to stay up to date in that niche not a year or more behind it. Now since you are playing older games you have to bring something to them that makes them interesting to watch, that should be your personality but since you decide not to speak you take away from that and that leaves very little incentive for people to stay, like, and come back for more.
Again not to hurt you or upset you just thought I should bring that up. Lastly try to sound a bit more energetic when you do decide to speak as it will help if you feel the commentary is to long try shorter episodes.
I hope I was of some help I'm not the best at sugar coating things s if I offended you I apologize but I did it to help you not insult you. Anyway good luck

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