I want to suggest that the default widgets need to expose some of the options that we have when we call the functions those widgets are based on.
- The archives widget needs to support limiting the list. My archives go back to 2003, but listing them all in the sidebar is just preposterous.
- The tag cloud widget needs to support limiting the list, and probably ought to specifying the upper/lower sizes, etc.
- The links widget ought to support the optional "flat" list, at least
Anyway, I think you get the idea.