Will clover work well as a groundcover?
Clover will certainly fill in as a ground cover, but may go beyond that if you aren't careful. Clover is an aggressive spreader in the right conditions (sun and moderate to dry conditions with low fertility soils) so be prepared for this reality if you decide to plant it. It also is a great bee attractant -- that is good or bad depending on your perspective.
Both white and red clover (Trifolium repens and pratense respectively) are both "nitrogen fixers". This means they make their own nitrogen from the air (most plants don't do this) so are perfectly suited to areas that receive no fertilizer and have low organic matter in the soil. In areas that are fertilized or well amended they will be less aggressive and spreading.
Clover can make a great ground cover if you know what you are getting into.