^ well, yes and no on the German/French Swiss part. The German Swiss usually aren't shy with adopting a Romand ('s success) as their own; reservations the other way around are usually bigger; also, Stan is actually half German (even including citizenship), as his father is German/Polish/Czech (complicated yet?), so there's potential for cross over appeal to Swiss Germans (although Swiss Germans often dislike Germans; maybe that's part of the problem).
i don't know whether or not the Romands are less into tennis than the German Swiss are. they surely are less (in number), in any case, so that might indeed be a small factor. but i'm afraid that even the Romands are less into Stan than they are into Fed. among other things, the French (even if they're Swiss French) will always be likely to prefer style over force. and in the end, we also have the personal life issues - Mr. Clean vs. Mr. I'm leaving my (celebrity) wife and newborn kid to concentrate on tennis (i know they're back together, but stuff like that just isn't good PR and usually sticks).
anyway, i think the real issue behind the Swiss' occasional lack of love for Stan is that they're spoilt by success. we shouldn't forget that right before the arrival of Fed/TMF, they had Martina Hingis on top of the women's game. population-wise, they're smaller than the Chicago metropolitan area - yet in 14 out of the last 17 years, there was a Swiss slam winner, and they held a #1 ranking for over 500 weeks since '98 (almost 10 out of 15 years!). it's the dilemma Roddick faced, only much intensified by how recent and how intense the national success was - and still is (let's not forget that Fed is still more successful than Stan even as of today). does that mean the Swiss don't deserve him? idk, i reckon it's not *that* much different in other countries for second/third/ tier guys. what about Tipsy in Serbia?
as for a dramatic victory over Fed? sure would be entertaining, but i have my doubts. you'd think that 2009 might have been a breakthrough in that matchup, but i still can't believe that Stan found a way to lose their match at IW, against one of the worst performances i've ever seen by Fed.