Making something from nothing is difficult, or at least, fairly expensive. But, that's not to say you should never try. Take The Rawls Course as an example -- I don't think it is one of my best courses, or even necessarily some of our best work, but to have a good course on campus was a noble goal, and we'd have had to go twenty miles out of town [or more] to find a site with any real character, so I think it was worth doing.
The "minimum" you should achieve on a project is up to the individual; I have high standards for myself. But I would say that the minimum any architect should achieve so that the project is worthwhile is that the course drains well and is fun to play. If it's not fun to play, somebody else should have done it.
Screwing up a good site is easy. I don't even know why that would be a part of this discussion. Doing the best possible job on a good site is not as easy as it looks, but if you are really good, you'll make it look easy.