IMHO -
ESPNC - Simply put all of the rerun sports on it that any particular person wants to see on it, they have seen. The library was simply too small. Most live sports before the 1980s were not saved, and the NFL had the sense to have the rights revert to it for its games. I am pretty certain there has been more coverage of the long forgotten USFL on ESPNC than there was when it was a going concern.
ESPNU - On college football Saturdays, and to a much lesser extent during college basketball, its a fine channel. Really just ESPN3. The rest of the time, its simply worthless.
ESPND - Memo to Disney HQ. The channel is in SPANISH. The number of households its in measured against in the general households numbers is is irrelevant. If its penetration in Spanish households is not what you expected, then that probably says that a lot of us who were saying the that mad rush by Disney and GE into Spanish broadcasting was shortsighted, as it was to take advantage of what is only a transatory era.
Disney would do best to just give up on this "college" theme for ESPNU and just call it ESPN3, and thus allow it to dip into other rights held by ESPN. ESPNC would be best as a "high number" digital channel, and ESPND is irrelevant.