I think all these responses are useful, to a point, but the original inquiry asks too much for what is possible and economical.
There is only one real solution to this matter, and that is:
1. In Switzerland, you cannot escape the charges (you'll get them on your mobile phone bill) for incoming or outgoing calls on a Swiss network, which you will have to have.
2. A triband is a minimal system, and all of the local carriers (Swisscom, Orange, and Sunrise) provide this.
3. Watch out for the unsolicited and unadvised automatic renewal on an annual or other period contract. If you do not advise you do not want to renew with a minimum of 90 days notice, you are on the hook (no pun intended) for another year for monthly basic charges.
4. It is true that Orange has the most competitive plans and is probably the most economical way to satisfy most of your needs.
5. You can't have your cake and eat it, too. The best combination is to live with the Swiss-supplied mobile and get a trunk overseas plan (via Worldcom or something similar) with a US-based toll free number or discounted international calls to Switzerland included. This way, you avoid the outgoing charges for air time from your kids or other US-based landline callers, though you cannot avoid the airtime costs on the incoming to your mobile. At least, only you will see the costs on the deadly monthly statement.
6. I have had both Swisscom and Orange, and have found that once you tell Swisscom you are quitting them because of higher charges, they seem to cave and offer better plans. I have avoided Sunrise, because my colleagues have had terrible experiences with them. Shedding Sunrise is similar to trying to get rid of old luggage...seems to stay with you for life.
7. What I do is to try to get people to call me on the mobile only in emergencies, and to leave a voice mail. If this cannot be done for one reason or another, I ask that they please call me on my landline at a convenient time. Costs for landline calls are pretty good from either direction to/from Switzerland, and even Swisscom has a good half-tariff plan, if you insist on it.
8. Skype is the best solution for lengthy calls.
9. Swisscom has a deathgrip on overall communications, as you will find in most European countries that they are behind the excessive, not to say usurious charges for hotel Internet access.
I think that Swisscom is trying to be more competitive these days, but, as they say, caveat emptor intro SIM (watch out, buyer!).