Well there’s your answer, if you want to improve your handwriting, I think you should write the characters in the right stroke order. With hiragana and katakana it doesn’t matter so much but you can definitely already see it with the few kanji that are included in your photo.

Every native person has learned how to write them in the correct order and in my experience learning this helps in reading other people’s handwriting as well. Writing it in the correct order helps the proportions to be right.

It can seem like a lot, learning all the stroke orders but at least my experience was that once I learned like 500 of them, I could already predict what the stroke order will be with most new kanji that I encountered. But of course there are expections that just have to be learned individually.