I see these topics pop up a lot, each and every time I’d love to sit back and post a long list of suggestions and explinations on why such things should be done in order to increase the graphic quality of your work.(run-on?) Anyway, I’ll say only a few things to not waste my time on something someone may not have any desire to read.
From your name, and as kusy said; you appear to be a fan of manga/anime which tend to use absurd styled weapons. From that I cannot relate so I will skip over the item and go to critiquing the sprite. For any form of art you must know the basics of art as a whole. Proportion is a key factor. Before you get into all the work of giving him hair and a killer shirt. You want to make sure proportions are all correct, whether it be thickening the neck, sizing down the head, shortening the torso and lengthening the arms. After having a solid silhouette of a character you should work on the depth. Unless this is suppose to look like a paper cutout of a character you should show the top of his feet, shoulders, and head. If you wanna go crazy, even give a lil depth to the hands, but we’ll save that for another time.
From there you’ll then start to consider your base skin tones, and the outfits you may dress.
Remember as well arms and legs bend.
Get back into it, hopefully one day you’ll be on the level of guys like Fool, Snake, and indigo. Best of luck.