I am learning kana and have some problems with similar construction. I found an excellent source (https://www.youtube.com/watch?v=TohUrbpdYJY) where Yuko sensei described a left-start and top-start concept that works for シ vs ツ and ン vs ソ. I suppose it's similar to the way > = and < are the same elements with a different orientation. I'm not able to find any similar distinction between い and り.
I can see that both have a similar J on the left with another stroke oriented to the right and left respectively. Is there something more I should be considering? How are these taught in Japan?
--------------Update------------------ I was able to find some help with this video showing someone hand-writing the hiragana. For now I focusing on the start, direction, and end of the characters in the 4-square graph. https://www.youtube.com/watch?v=hSQi34uKMmY
I also found this set of instructions which does show progressively worse examples of 0i until you end up at ri. http://japanese-lesson.com/characters/hiragana/hiragana_drill/hiragana01_writing.html