The amount of business needed in the art business depends on the artist's personality and how vulnerable she is to external circumstances. Distraction of any kind, can hurt the art making process, whether it is the actual act of painting/sculpting being interrupted, or the distraction of the changing of the mind in midstream and producing an inferior piece because of it.
And the business side of art does both, and it is important to pay attention to that. The sobering thing you should keep in mind is that business IS the other side, the other half, and to some, it is indeed the better half. Doesn't mean that they are worse artist for it, just that for them, it is the side that leads their whole enterprise.
Many art masters had a very astute business side to them (Rembrandt, Picasso and many more) and were not affected by it negatively, but used it to their advantage.
The problem incurs when artists and even galleries start to lead with their business side too much and now their art side, the connective side, diminishes which is just as detrimental as if things were the other way around - not getting involved with the utilitarian and vital business side.
The business of art is much like the business of life (everything is kind of business actually) - utility and emotion coexist and forge ahead together, otherwise it's not going to work.
But one has to be pulling and the other must be pushing. There is no side by side, because they are so different. Kind of like mind and heart. Balancing thing is such a vague term, and can mean anything. So stop balancing the two. Instead decide what you haven't been doing enough of, and do that. And let the side that is more of your personality be the lead, the puller, and the other side be the pusher. The one that excites you more is the one that is more you; do you like seeing your art being bought by collectors or do you like getting the painting just right, more. That's how you know!
For those artists that might think that they don't like the business arena or that they don't have it in them, it is simply not so. If you like having your art exhibited and it be sold - you like business and you are probably fairly good at it. You just have to try!
To turn things around we need to do more of what we haven't been doing and let the stronger side of us lead, and be in the front. But make sure that other side is pushing, or it won't work. If you rather deal with business first, then do that first unapologetically. If you are more of a connect and feel first, rather than utility type person, then by all means lead with your feelings. That by the way, the way of feeling, is how you move the hardest of mountains, just in case you were thinking that emotions were somehow less practical or useful.
The amount of biz needed is the amount necessary for the courage to kick in and put it, the biz, in the right place first of all, and then make sure that it works in unison with the other side of you, your feelings - Your Art.