I'm wondering how long you've been studying Japanese.
Japanese is hardly primitive. It is highly expressive: in fact, in many regards it is more expressive than English (or Russian). For example, the use of honorifics and keigo make clear relationships between people that is not possible in Indo-European languages in the clean straight-forward manner of Japanese.
Japanese is more explicit than Indo-European languages in expressing how you come by the information:
All three sentences could be simply (primitively) translated into English as "It's going to rain." But the first sentence conveys that you got this information from someone else; the second sentence conveys your impression (perhaps you see storm clouds gathering); as for the third sentence it might be technically correct to translate as above, but it's really only appropriate for expressing the fact that it's raining right now. Because of these differences the above three sentences could be translated as
I hear it's going to rain.
It looks like it's going to rain.
It's going to rain.
But in English we aren't that particular. We might just say "it's going to rain" whether it's our impression from what we observe or whether we learned it from the weatherman on the radio. And, so from the perspective of Japanese, there's a degree of ambiguity in the English which would lead to the question, "how do you know?" In Japanese, those three sentences are very clear about how you know what you know.
Sentence ending particles, and such, convey a great deal of information, again in a manner that is not easily expressed in English.
While without any further context, these would all be translated as "it's fine." In Japanese, there are subtle differences, particularly in the use of ん, that are just not translatable.
The following two sentences most likely are not being said by the same person:
The first is probably a woman, and the second is probably a man. ("Probably" because if you're in the LGBT community, you might be speaking in a different register.) And then if you change the particles:
I wouldn't begin to know how to translate the differences in English without the English getting clunky, ackward, and unnatural. But they're all natural in Japanese; each with a slightly different feel or color to it. The best we can do in English---avoiding clunkiness---is to say, "It's beautiful" and let the context
convey the rest.
English is very good at conveying information in a straight-forward and objective feeling manner. Take again, "it's going to rain". In English, and other Indo-European languages, we don't really care how you came upon the information. Looking up at the sky and seeing storm clouds or hearing the weather report, either way it's going to rain. So, in English, our attitude is not to get bogged down in the details of how you got to know what you know, just "shoot it to me straight". But these are cultural and linguistic differences. They point to different perspectives about what the various languages deem is important to communicate to others. These are not short-comings in the expressibility of the languages.
And as for vocabulary, Japanese is highly expressive. Find a good Japanese dictionary (written in Japanese for Japanese) and you'll discover the rich variety and subtly of the language. Try reading Yukio Mishima in Japanese, and look up those uncommon or strange looking kanji; often he chose those characters not just to look literary but to go after subtle nuance in feeling or meaning. "Sound of waves" in English, while an entertaining story, comes out rather flat compared to the language Mishima used. Comparing the two side by side, a Japanese person might remark, "English lacks the depth of expression we're capable of in Japanese."