I want to write a light hearted story but, can't. Trying multiple times I failed at it, and its hard when mainly writing darker ones.
I want to be able to write an Ace Attorney legal crime drama.
But I'm too lazy to look up law facts, they are so boring 
I'd really love to be able to write a fun and meaningful children's comic/picture book. I'm a huge fan of picture books and children's book series, especially the ones I remember growing up with, like Frog and Toad, Arthur, Henry and Mudge, Barbar and Madeline. I feel like every time I've tried to come up with a cool idea, I always manage to touch on more mature themes with it--which isn't to say that children's stories don't touch on more careful topics, but there's a certain grace to go about it and I always end up...just basically making a teen/young adult themed story. 
Hopefully one day I can try my hand at it, though. There was a time where I thought I wouldn't be capable of writing mystery and thrillers, but after some practice and lots of inspiration and research, it turned out I was able to grasp it, so there's no harm in trying!
Standard romance. I always end up making it either the secondary plot, or adding something very fun and fantastic to the concept, I don't have enough socialization and dating knowledge to feel like I can just do "they meet, date, like each other" scenes.
Short stories ;_;
I'd also go with thrillers, because I'm in that hard in-between of not liking stories that are too simple, but also not liking stories that I'll get confused if I take a break in the middle of reading/watching. Yeah I could do a web of lies as a story but also I'm gonna forget about key points while focused.
I really want to write some kind of a detective story with shades of thriller. I want to be able to create stories that would shock my readers 
I've always wanted to write a horror comic, specifically mind-bending, psychological cosmic horror similar to Junji Ito's work. Except, I suck at horror (probably because I don't really read a lot of horror stuff in the first place, in fact, I'd go as far as to say I dislike most of the mainstream/popular horror stuff that gets put out all the time, the only one I really like is Junji Ito), and also my art style isn't really... horror material?
Human stories.
Almost all my stories and story ideas are based in one fantasy world or another with magic or powers or something supernatural but writing plain humans is tough. I worry about things being too boring or cliche and it's one of the main reasons why I've yet to make any developmental progress on the one human story I want to tell solely for fear of not doing it justice.
Maybe something with a dark comedic overtone. Like a guy that's be kicked around by life too much and just can't take it anymore. So every encounter he come by with anyone, he either beats up or kills just because he did not like them. For the violence part of it, it would be anything cartoony, the gore in this will be ramped up to 110%.
I would love to write a mystery, but I don't think I could put it together without the answer being obvious!
As far as super niche ideas, I would love to write a comic about a high school cross country team, but I don't think there would be much of an audience for running related stories. Maybe that will be a 'for me' project in the future haha
Romance and slice of life for me. I'm not really good at doing romance at all. Smut? Yes, I can do that just fine. But romantic, lovey-dovey, kissy-kissy stuff? Yeah, I can't do it. I'm really bad at it irl too so lol.
And I think my main problem with slice of life is that I get really bored with it. It feels too 'mundane' and normal. I want to write so that my imagination can go crazy, not write about me sitting here struggling with my average life and the average things I get up to.
Really weirdly and specifically (other than magical girl webcomic) I really want to write a card game webcomic because I remember watching this video1 when it came out which the tl;dw version is: why are card game anime not actually about playing card games? Just write it like a sports anime, lots of people enjoy those without knowledge of the sport and lots of people irl play tcg without magic forces, so there's something there. And I looked at my pile of trading cards and went "he's right someone should do that" and then realised "hey I should do that". And then proceeded to not do that because designing a card game on its own is ridiculously hard but I don't have the confidence to a, make it engaging enough to grab people without magic forces or who aren't into card games despite being told character driven is my strong point, but b,I'm really not sure how much of an audience there would be. Basically, yay nerves..
A show that managed to do this surprisingly well (but using the card game as a one-episode thing) was Craig of the creek on the episode "bring out your beast".
For a while I wanted to write a story with two main characters who are separated from each other from the beginning of the series onward. But I want the story to be evenly split between them and I still haven't figured out how to actually do it.
i would love to write stories with darker themes and it seems conflict/war-like situation is a topic i'm willing to write about. also with different perspectives from different characters. but as of right now, i'm currently practicing, in a way start from the fluffy ones, like leveling up or increasing the level of difficulty which each novel that i wrote and finish (hopefully).
