@karen One of the things I find the hardest in Japanese is actually the lack of spaces, I struggle to know where a word/particle ends and another begins.
@karen Well I "read" with kanji. But still, I struggle to know if a bunch of kanji together are a single word or many. Or if the hiragana are particles or part of the word conjugation. は vs が may be difficult to write/speak, but I don't think they are a huge problem for understanding. And kanji are difficult but it's easy to find what they mean online (and most of the things I read have furigana).
I'm talking about understanding Japanese. So this is probably not true for writing/speaking :).