Here we get ever so slightly touchy feely. My outlook on life (and all it includes eg managing people) is this:
The meaning of life: Relationships
The essence of life: Gratitude
Everyone is different
We like to be able to categorise people, preferably into 4 neat pigeonholes, but my experience is that no two people are alike (not withstanding ShiftHappens slide 5).
We love the simplicity of Myers-Briggs and other psychometric tests, and they can useful. However I think they are only an accompaniment to really understanding your people.
So, instead of creating categories (analytical vs creative, left brain vs right brain, defensive vs temperamental, etc), have a special black book on all your staff.
Keep a Black Book
In this little black book you should note down:
Refer back to this book regularly, to remind yourself of strengths of your team, plus things to send their way.