You might not realise it, but these days the towns you mention are pretty much Zürich suburbs.
If your wife feels isolated or lonely she only has to jump in the car or on a train - she can be in the city in 45 minutes, in Rapperswil or other lake front destinations in less time.
Although she likely won't feel isolated or lonely - Wollerau and Pfäffikon are choc-a-bloc with foreigners, language should not be a barrier to finding pleasant acquaintances.
Officialdom is largely German-only, your wife might need some help getting set up. But in those towns that help can be purchased... find a good relo agent.
Once she speaks a bit of German if your wife is the outgoing type she will find plenty to do.
I saw the lack of English (my village was at the time not as cosmopolitan as the towns you mention) as a plus in that I would be forced to improve my German. Your wife will benefit from living (some of) her life 'auf Deutsch', something one might lose motivation to do across the lake. And given that she will need German for permit renewals in the coming years, why not get a head start?
The whole Zürichsee area is accessible from Ausserschwyz. Don't think only in terms of what is available in a particular village but rather what is available within reasonable travel distance. Lots on offer scattered around the lake.
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After 15 years I have mixed feelings about the area. I moved here because I wanted to live in a farming community. All these years on, the village is no longer farm oriented, it has morphed into Zürich dormitory suburb - as have most villages commutable to the Big Smoke. My once-sleepy little village is a tad too crowded for my taste these days. Sic transit gloria , and all that.
But the most important thing I need to live as I wish is right to hand here in the village, so as long as we are in Switzerland I will stay put.
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As with everything in Switzerland, YMMV. Perhaps if you could tell us a little bit more about what your wife is looking for in a community we could offer more concrete advice.
All the best...