White would be my first choice, but McKenzie would be fine too (though I just have this feeling that his public quest for the job coupled with apparent animosity between the ARU and QRU, he may just end up getting overlooked).
Out of interest, why White over Ewen? I completely agree that his world cup win is a massive boost to his CV but I feel as though it's really Ewen's time. He's been assistant to one of Australia's most successful head coaches. Ever. He's led a massive revival at the Reds not only on the field, but culturally as a team and as a Rugby Union (I agree, White has done this as well but the Brumbies had only really been off for two years, Reds had been in the cellar for quite a while).
I can see that this will be viewed as quite biased (Reds supporter and Ewen as the Picture), but to some degree I feel like Ewen not only deserves it the most, he also wants it the most. White has 'expressed interest' in the role, whilst we have a home grown, Wallaby Prop, genuine Aussie bloke so keen he has already made it clear he's walking out on the reds at the end of the year and knocked back at least 2 international offers and a request to return to the Reds. This guy wants it, and he wants it bad.
The credentials are there, he understands how to manage players and win titles, beat the bloody kiwis and develop a new game plan when it is called for.
Don't get me wrong, Jake is an absolutely brilliant coach. He has shown it time and time again through the Brumbies, a Tri Nations in 2004 and a World Cup in 07, but we have gone through with the foreign experiment once and it hasn't really worked out. Why not go back to someone that knows the ins and outs of Aussie Rugby? Someone who can build a serious support network around himself in Australia and call on the knowledge of a Lions Series as a coach (plus much more) and a World Cup as a player.
For me the answer is obvious. But I think your comment about the tension between the ARU and QRU is also true... And E.M. may end up being a casualty of that.