That's about as simple as you can get with abstracted quantitative measures of pretend humans. Some might say that you don't need Heart, but they're probably not much fun to play with.
These six attributes are like a beautiful nerd haiku. They not only carry tremendous nostalgic weight, but they're pretty brilliantly flexible. This is the porridge Goldilocks ate.
Yech. Anytime an attribute list gets too long, I start backing away. This is a more accurate depiction of the sort of competencies I test for in my games, though.
Á la Carte Expendable Additions
Depending on the campaign, one or more of these might be helpful. These can be used as roll-under attributes, but points from them may also be expended. F'rintsance, You may roll Resources to generally see if you can acquire the items you need, but your castle burning down may cost you several points, or you might willingly spend points to acquire something rare and remarkable, like a magical artifact. And, of course, you lose Sanity points when you fail a Sanity check, and can probably spend Sanity to gain insight into horrible things.
This takes a page from Star Frontiers, with its paired attributes.
Roll 3d6 for each root attribute. Exchange as many as two points between attribute pairs. Maximum of 18.
Assign 8, 10, and 14 to each root attribute. Move as many as four points from one half of a pair to another. So the maximum spread might looks like: