On this atleast I agree with jeske, we pay a huge amount for vehicles that can't do anything everyones elses vehicles can do for half the price, or less. The change to disembarkation pretty much neuters Banshees, Scorpions and Harlequins as well and makes Fire Dragons a lot trickier to use especially if they have some longrange artillery armour that can shoot from accross the board.
Rhinos may be fragile but at least they can still be used to provide ablative armour and mobile cover. Dark Eldar actually benefit quite a bit, their vehicles are no more fragile really but they can deal with enemy vehicles more effectively.