To answer your question you should clarify what "important" means to you - it's a very relative concept. Example: If I had to chose between family (representative of a group) and a best friend (=individual) I would have chose a friend - but that is purely on "instinct". Objectively looking a family aka group would be a much wiser choice (more support, moral and financial; always there...). So, which criteria of "important" would you pick?
Groups are nothing without individuals, but it would be very difficult (if not impossible) to survive without the group. We would certainly not be conversing on the Web right now if the group were not so important.