"Japanese is a little hard."
Yes, according to the FSI studies, Mandarin is also one of the most difficult languages, as well as Korean, Arabic, etc., but Japanese is the most. Remember, this is a statistical result, depending on individuals, not a precise scientific conclusion.
The written form of both Mandarin and Japanese (mixed with many archaic expressions, idioms... ) differ greatly from colloquial, that means the difficulties will only increase as long as you continue learning them.
I think, for me, Japanese is easier to learn than most other languages. I took French for ~12 years throughout school and University, and while i can get by, i was never super good. The problem holding me back there is that i have not be immersed in the language (like lived in france for a month or something).
Japanese on the other hand has a ton of things to learn, but since i am a weeb, i can get a partial immersion of the language while watching anime and whatnot. Im having a ton of fun learning Japanese, whereas learning french was like an obligation. I've only been learning Japanese for like 6 months, and i look forward to learning so much more! ^_^
I think Russian is hard. Possibly even harder than Japanese. There are so many different variations of how you can say stuff not to mention cases and conjugations and genders and it's all different for plural form. I've never heard a foreigner speak Russian correctly regardless of how long they've been studying it. Sorry for the rant.
What you said is not rant but very interesting. Да русский язык крайне сложный, и сколько лет ни учишь, все равно допускаешь ошибки всякие, но
1. Согласно FSI, японский язык является самым трудным относительно носителей английского языка. Для, скажем, тайванцев или корейцев, японский проще русского; а для сербов или поляков, русским относительно легко владеть.
2. Мне кажется, русский сложен не из-за множеств выражений, падежей, родов или чисел, как Вы сказали (это характерно и для других славянских языков) , а из-за огромного количества исключений, в том числе ударения.