Well I'll give you my 2.5 cents here as someone also trying to make it in gaming, so I'll throw in my opinions and general advice I've gotten over the weeks;
First off your channel profile pic and the banner are not great, kinda looks like something made in paint (and not in a cute way - like gradeaundera), so as soon as possible should look into either buying a set from some of the talented graphics designers here on the forum, or just use a pre-made template that you can find on youtube (tho you would need photoshop to edit them in most cases) (if you do have PS tho, then you can edit them, tweak the colors and so on...)
Basically it just makes everything look more professional, adds a lot more quality and so on...
Now the thumbnails, for the most part they're alright. I can see your style is to have extreme text placement and then lesser imagery, is that a good thing or a bad thing hard to say. I'm sure some would like it more than others. It's something you can work on over time anyways, just continuously polishing your own style of artwork and such.
So moving on to the bread an butter of the channel the actual gameplays;
First minute into the video, it's super boring, you sound like you're at gunpoint and just forced to play it. Very bored sounding tone to your voice. Whether that is the case or not , dunno, but with no facecam the viewer has to go with what the voice is showing, and it was showing me that you're already bored and the video just started. Then skipping through it there's a lot of empty spaces where there's zero commentary at all, and overall it's making me wonder do you want to be somewhere else.
First 30 seconds are better as far as energy goes, but then you get lost in your own commentary and the beginning stretches out for another 30 seconds before the gameplay even starts, which is not a good thing to attract new subs. Skipping ahead the game chops and lags a fair amount, which makes me think you're trying to play on high settings but your PC can't handle it and the recording, so you have to find a better balance between that. (It happens to all of us, so shouldn't worry too much, but you definitely gotta fix it)
Overall the Action Henk video I found not watchable due to all the choppiness and lagging, it would help a lot if you had much more enthusiasm while recording, and practice with editing more so videos aren't too long, and to not have a lot of pauses in them. Cutting out parts that don't offer entertainment and so on...
Hope I'm not too harsh, not trying to be mean here, those are just my general concerns with the content as a viewer/creator. Keep on working on it and I'm sure you'll improve greatly.