@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 :).
@karen Yeah for sure, I guess at this point my Japanese level is just too low xD
To reuse your example, if you're more proficient with particles it will help you, among other things, with recognizing word boundaries