Well said HDNitehawk. My wife strongly agreed when I showed her your reply. I like JRWs idea though. :-)

Steve be assured that getting such a wild card from my wife was quite tough :-)

Back to topic: Is the 300 really drawing so much unwanted attention? That i would consider a negative aspect.
Why would you stick to the 70-200 for the wedding? Versatility? I was thinking of the 300 during the ceremony which is going to be more static and switch later on. Of course you could argue that in those cases you wouldn't need the 2.8 but bokeh and ability to use the glass also for sports would be my answer.

500 is no option because I would prefer the 400 2.8 over the 500 because it is faster and for both you would need a mono or tripod. And you are right: the long end is missing. But here we are at square one 300 vs. 400.

At the moment I am thinking get the 300 and maybe next year the 200-400 which would cover the long end perfectly. But that would mean again a lot of hard work to get my wife to accept that. But let's not worry about future trouble ;-)