I think you hit the nail on the head. While you may dislike MacKay for being like or for truly being "old guard", he is the best hope for a majority Conservative government.
The best you will get with Harper (and I hope I'm wrong)is a minority government. And, if you didn't like the old Tories you'll hate the watered down, cling to whatever vestiges of power we have minority conservative government.
As a minority, nothing and I mean nothing will get done without the liberal boogeyman crawling up from the parliament floor.
To regain a majority the old guard and reformers like yourself have to come to a truce. Much like how the conservative christians and moderate repubs took the house, senate and POTUS. Not everyone likes it (heck half the time even this board can't agree on anything), but it worked.
Smart Bartender
A man enters a bar and orders a drink. The bar has a robot bartender.
The robot serves him a perfectly prepared cocktail, and then asks him, "What's your IQ?"
The man replies "150" and the robot proceeds to make conversation about global warming factors, quantum physics and spirituality, biomimicry, environmental interconnectedness, string theory, nano-technology, and sexual proclivities
The customer is very impressed and thinks, "This is really cool." He decides to test the robot. He walks out of the bar, turns around, and comes back in for another drink. Again, the robot serves him the perfectly prepared drink and asks him, "What's your IQ?"
The man responds, "about a 100."
Immediately the robot starts talking, but this time, about football, NASCAR, baseball, supermodels, favorite fast foods, guns, and women's breasts.
Really impressed, the man leaves the bar and decides to give the robot one more test. He heads out and returns, the robot serves him and asks, "What's your IQ?"
The man replies, "Er, 50, I think."
And the robot says... real slowly... "So............... ya gonna vote for the Liberals again?"