So first off, I personally think you should be focusing your efforts into one of these versions. Either black and white or color. The fact you're updating both is actually kind of unreal levels of impressive, but it unfortunately doesn't mean that much in the eyes of the editors. If they know both versions exist they will certainly be impressed, but in my opinion the amount that they'd be impressed is not worth the extra effort you're probably putting in to update both. They'd be more impressed if you took your most popular version and made longer and higher quality updates instead, with that time.
In terms of art, with your style, I think you're sitting right on the line of what they accept for Featured. Since they have a lot more leniency with more out-there styles, you have more breathing room. But at the same time you're in Drama/Slice of Life which composes most of their most popular webtoons (True beauty, lookism, etc) so they're not really looking to fill up this category other than with titles that have exceptional everything, or some really unique spin. Remember that a lot of titles they're carrying over from Korea are basically majority SoL/Drama so you're also competing with whatever Featured webtoons on the Korean site that WT wants to transfer over. Basically: Competition is absolutely brutal.
Since I keep talking about the demand of certain Genres, I might as well make a list of my own deduction of generally how hard it will be to get featured in a genre, starting from hardest to easiest, using the canvas genres:
Romance = Comedy
Slice of Life = Fantasy = Drama
School
Sci-Fi
Action = Superhero
Supernatural
Horror = Thriller = Crime/Mystery
Heartwarming = All-ages = Animals
Post-Apocalyptic = Zombies
Historical
Inspirational
Informative
Sports (I feel like this genre in particular is one where they are looking for fresh blood but not many people are delivering)
Anyway, yeah, I hope me listing this out makes it clearer why it's so hard to get featured in the top categories- Because there are so many layers beneath it that they need to prioritize to get more of that certain thing on the site. The top genres are packed on english speaking webtoon featured, theyre packed on korean featured, theyre packed on canvas on both sites, they are P A C K E D.
In terms of what you could improve, I really think you should go in hard on the art. Like I said, it's passable, but it needs to be amazing. The art style that I draw the most parallels with on Featured is the webtoon "AXED", because you both have this sort of cartoon style and a similar wide-style of drawing faces.
AXED's art is extremely clean. No fuzzy lines, no color bleeds. This is what they're expecting- Extremely clean work. The colors they use also are not muddy, and pop out despite still having an earthy tone. I would study lots of other artists on Featured with a similar cartoon-inspired style and look at how they choose colors and draw strokes.
As for the story, I was mildly interested, but it's not enough to leap past your competition.The first three episodes were very slow and VERY slice-of-lifey, which like I said before, is already super abundant on featured. I think it could have been improved a lot if we got to see what was under his mask in episode 3 as well, as that would leave your third episode with that essential "hook" because people would want to know why he has those scars.
Anyway, good luck!!
Also edit to everyone else, I will be mega slow with finishing reviews since I'm behind on work and have something to do for my other job (so i wont be near a computer to do edits), but I will get around to them all eventually!