Should I focus on JLPT N3 or output if I only have 20 minutes a day?

I'm a busy professional struggling to balance exam-focused study with practical Japanese. I want to see measurable progress, but I don't want to end up being a 'paper tiger' who can pass a test but can't hold a conversation. With such limited time, is it better to grind kanji readings and vocabulary, or should I spend my time on short conversation drills using a tool like Chickytutor.com to ensure I'm actually using the language?