From my limited perspective I am thinking that maybe the SH purchase is the right decision. Canada has never been a first day participant in any allied operations and will not undertake aerial strike on its own against another sovereign state. So in support of our commitments to Canada, where there is no likelihood of fighter on fighter operations above North America, the SH in any variation is more than a match for anything that will be of interest requiring an armed response. I have said it before I believe we need a low end prop type to support a variety of tasks and now the USAF is starting to look seriously at that same fact.
So if I may offer a suggestion maybe we will end up with a fleet of SH and Growlers to support a niche role within allied operations and for home protection along with a fleet of armed UCAVs and prop types for the low end of the spectrum.
We will never face a RED DAWN type of invasion nor is there a chance of invasion over the top via the Arctic. We need to be realistic here. Canada is too distant from any potential battlefield for us to get our assets into place for the first day. We have to realize this.
SH will work for us. The USN will likely purchase more as will others thereby ensuring that the type will be fully supported for decades to come. As nice as it would be to have all the fancy top of the technology line equipment we can not justify the purchase of the likes of F35.
Unfortunately Canada's requirements differ from what you have said here. The requirements you have outlined here could be met by an F/A-50 so where is the cost comparison between F/A-50 and Super Hornet if we are going to be honest and fair?
As for Canada 'never' being a 'first day of war' airforce, I think the RCAF would fall about the place with laughter over this. I suspect you are a bit young to remember the NATO operations over Kosovo, but Canada participated with Hornets from day one, right in line with it's NATO commitments...
http://www.journal.forces.gc.ca/vo1/no1/doc/55-61-eng.pdf
Canada also deployed tactical fighters to GW1 and operated as close to 'day one' of the war as any of the Coalition...
2011 Canada deployed tactical fighters to Operation Mobile over Libya and were among the first to be flying combat operations over Libya. The list goes on and on but shows the ridiculous argument that RCAF isn't a 'first day of war' airforce and can't deploy because they are 'too' far away (though of course the same distance as the USA...)
As for the 'won't ever conduct strikes against a sovereign state' they did in fact do so. Yugoslavia was a sovereign state. How can you categorically say they will never again do so? That is the point of buying defence capability. You buy it because you DON'T know what the future holds.
If Canada buys Super Hornet due to political reasons, it is locking itself in to an earlier generation of combat capability that has limited long term growth options. Canada will be flying these in 2050.
Think about that reality for a bit...
I am a fan of the Super Hornet, but do I want the RAAF flying it in 2050? About as much as I would want RAAF flying Mirages today...