I think the BBC misunderstood why the Clarkson show worked. It was three friends larking about and entertaining the viewers. The format developed from this, not the other way around.
I think to replicate the Clarkson show was the wrong decision, it created expectations that were never going to be met. I think the presenters have improved throughout the series and it is more a car show now, but the bits from the old show detract. Someone needs to be brave enough to invent a new show. It has been a car show in the past, but with a minority audience, it seems to be heading back that way. For car nuts, we'll probably love it, but for a mass audience it will miss the mark.
So now the challenge, invent a new show, with the theme of cars running through it, but not necessarily the main theme each week. Having presenters that gel together will help. So anyone have any ideas, send them to the BBC, make yourself a fortune.