I've watched quite of lot of Sky coverage this year (don't ask me how) and the thing that strikes me is that Johnny Herbert and Damon Hill really have nothing to say. They seem to search for words all the time and don't bring anything to the broadcasts.
This is the only point with which I'd take issue. It's very unlikely that a broadcaster is going to find a really good F1 driver who can broadcast well. I don't think it matters a jot — after all, I don't have a problem with you or anyone else judging the abilities of the respective Sky and BBC broadcasters without being a broadcaster yourself.