Hi, haven't done this in a while so please forgive me if this isn't as good as the other icons in this subreddit.
Flame of Recca v1: Preview | Download
Flame of Recca v2: Preview | Download
Only did Flame of Recca tho, sorry if you waited 2 months lol.
I like the bright colors as well as your logo placement. I like that you've make the back folder distinct by using shadow and different images with different perspective. That's something even a lot of regular creators don't do. I like that you used background images that don't clash or distract too much (like faces or text). I like that your colors work well together and don't get too busy.
I think the outside edges of the whole thing look a little stark/pixelated though, maybe that can be softened or given a darker edge somehow. When it comes to character render choices, you sometimes don't have many options, but I would have your character stick out more or sized larger. If it's small because of render cut-offs, look for (or make) a different render, or try to hide the cut-off with the logo. You might also consider including more than a single character if you can find a render and it doesn't clash too much. That's about all the concrete things I can think of to improve on except for looking at other people who have made things you like and taking inspiration.
Some of my personal favorites include /u/Dalathan's Death Note icon, /u/lmbrt's Hai to Gensou no Grimgar icon (even though they do the thing that really bothers me where the background carries over to the back flap), /u/Janiebby's Nana and Silver Spoon icons, /u/Marx-Cartoonee's Serial Experiments Lain icon, /u/ozzi9816's Hanamonogatari icon, /u/animerection's Shoujo-tachi wa Kouya wo Mezasu icon, /u/vampire-wolf01's Pupa icon and Shakunetsu no Takkyuu Musume icon (busy backgrounds, but with their signature bold edges it has a comic-book-like effect). Also pretty. much. anything. that /u/pharrelle's made. Seriously, pharrelle's my hero.
Anyway, welcome aboard! New blood is always great.
"Hai to Gensou no Grimgar" folder icon. Haitogrimar
Folder template by fragirle. Serial Experiments Lain
Noticed this one doesn't have many skins for it, so I made one! --- Folder bg by emothic-stock.deviantart.com/a… Kanbaru render by otaku-re... Hanamonogatari Icon
Edit: Updated to a larger version Pupa
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