Your vocabulary is 70% of your language.

You can be good at grammar but what's the point if can't use words.

Do you agree?

Well.. In my opinion you must to know what is your goal. If you want improve your speaking skills then you need to focus in vocabulary: you can make some grammar mistakes in your daily life but the native will understand what you want to say. However, if you want improve for academic or profissional purposes you should focus in grammar because your colleagues and boss/professor will check your grammar all time. It is also necessary a good basis to read scientific articles and books.

Of course vocabulary

Honestly I don't think that's a good strategy. I only look at grammar points if I am really curious about it, or generally because I am having trouble expressing myself in that tense. For example, if you want to make a hypothetical point, you might need a grasp of conditional tenses so, that's fine. But it serves a purpose, because you struggled with it trying to speak to someone (or to yourself, even) or if you're trying to write something and can't because you need some type of tense, or whatever else.

Otherwise, I think it's not useful to look at grammar. It's much better to spend your time listening to things in your target language, reading, and generally getting a lot of input, a lot of material. It's also important that for the most part you understand this material, at least the basic ideas, otherwise you have to scale down a little and try with a simpler text/audio. That's all there's to it, at least in my experience.

EDIT: I forgot to mention why I think it's not a good idea, hah. I'll try to make it short: because for the most part no one remembers the grammar point when they actually need to use it. That's the honest truth. Even if you did, will you ever really stop to think when talking to analyse a grammar point? By the time anyone does that, our conversational partner is long gone :D

I'm not saying don't study grammar, I'm just saying there are probably much more cost-efficient ways to spend the limited time we generally have to study! Hope this helps, cheers.