Hey bro, I see you didn't change anything to your previous video yet (the one one with the Red Button).😮
Anyways, let's look at this thumbnail: I think in this thumbnail the attention should be more on the rappers. Maybe here you could NOT include your face, and just put 3 of the famous rappers there, and this tierlist on the side.
I understand, until now you put yourself in every thumbnail (and you take up at least 50% of each thumbnail). And the bigger you become as a youtuber, the more face-recognition you will have. But now, I think it would be more clickable for people who don't know you to have 3 of those rappers in there. Cos if you see this thumbnail on the phone, the only face which is visible in glance is yours, not the rappers in the background.
About the video: I dunno, the first thing I notice is that you say 'nigga' 10 times in the first 30 seconds (didnt count it, but it's just all I hear). Something to think about. It can put people off if you say it a thousand times. You can also go word words like 'bro', 'dude', 'man' to change it up a bit. (i am mixed white&afroamerican). I get it, you are still young and this is the "rap-culture", just keep it in mind.
For the rest: in the background I would have done a bit of music (soft beat), and maybe sometimes give some info about the rappers. Who is who and why do you put them in that position. Just sometimes, otherwise it would be too boring of course (just like you did with the one called BlueFace, you gave tiny bit of reason).
Okay I watched 8:00 of this video and my conclusion: I heard 'boy' maybe 3 times and 'nigga' like 300. Manmanman