Defaults for Configuration
Configuring EntLib is still very verbose. The config builders allow you to provide meaningful default values for many cases. E.g. logging could be done by something like
var builder = new ConfigurationSourceBuilder(...);
which will setup rolling file logging to a file named default.log with the default message formatter etc.
Sebastian Weber commented
Same goes for exception handling. I think rethrowing the original exception is a better default than throwing "exception handling not configured" exceptions at the user.