There are three primary dualities that are encountered in this discussion. The balance must be found not between any two points in a plane, but between the two poles of every dimension, and each one of these dualities adds another to the argument.
The first is between elitism and populism. The “exquisite design” or “minimal interface”, appealing as they may be, are elitist attractions. Only individuals and those with artistic / design bents can appreciate the effort. Collectives and those in a hurry would much prefer functionality over design, and design does get in the way at times; if not in the way of interaction, than at least in the way of fast delivery.
The second is between collaboration and control. Here is where the user freedom and expression comes in. This is (arguably) the reason why MySpace died, because it toppled the balance by giving too much freedom to the users. But this is also why Windows Live Blogs were shut down and migrated to WordPress: they weren’t doing enough.
The last is between the artist and the viewer, the creator and the consumer. All software is functional: it has to be. It provides a framework in which people can do things easily and meaningfully. Successful software is not just a contract, but a brainchild which needs nurturing and support by both parties, be they system devs and app devs over a platform, or socialnet devs and users over a website. The creator needs to provide direction, and the consumer needs to provide energy. This is why, increasingly, we are using the terms “responsive” in design: because there needs to be greater harmony between the two.
Ultimately, the cost of detailed design is ignoring your users, while the cost of listening to users is ignoring yourself. As two paddles to a boat, these must work in harmony to move the boat forward. When listening to users becomes too loud and unproductive: trust your gut and pay attention to design. When design starts to slow the pace, pull back and listen to your users, have fresh eyes look at your work. True balance is in those products that can listen and trust this rhythm.