Anything you can do to omit a single point of failure is a good thing so utilizing two UPSes for the redundant power supplies makes sense.
Agreed. Make sure that both UPS are the same, and that both get new batteries at the same time, etc.
Additionally, if a UPS is plugged into a surge protector power strip, as opposed to being plugged directly into the wall, does this diminish the effectiveness of the UPS in any way?
Yes and yes again. You have to treat the UPS as a surge protector in its own right because that's what it is. So if you plug a surge protector in to a surge protector, the surge protector connected to the wall is usually going to have other things connected to it as well, increasing the chances of this surge protector failing (and I'm not just talking about the breaker part of it popping). This is also called daisy chaining, and is a big no-no with most Fire Marshall's and laws. It's a big fire and safety thing.
The two UPS can be on the same shore-power circuit, that has no effect what-so-ever with what you are trying to do. If a breaker needs to be reset, you should be able to do this in about 5 minutes (or at least your client). If it is something else electrical, then you have another whole host of problems that probably wouldn't matter (like bad wiring). Always remember that an UPS gets plugged straight in to the wall. If you are that worried, get a line conditioner installed or advise the client to get a line conditioner installed. This will clean the power before it reaches your PDU/Breaker Box. But in most cases, it is not needed in the United States. If you are worried that having two UPS on the same leg of wire/same breaker and causing power related problems on that leg, you can do one of two things:
1) Upgrade the breaker from say 15A to 20A, or 20 to 25A. In most cases however, you'll have to upgrade the wiring as well.
2) Install a GFI Breaker and GFI Sockets.
Personally, I prefer GFI sockets over non-GFI circuits for this reason: I'm most liking going to trip the GFI before the breaker. While it's semi-common to not common, I don't prefer to install a 10A GFI on a 15A breaker. Too many problems with tripping the GFI can occur. I also prefer to install GFI sockets with an LED indicator. Usually the LED is lit only when the circuit is closed, that way I only need to look for an LED that is not lit.
You'll need a licensed electrician for all of this, unless you are licensed for HV.
In my house, personally, all lines are 15A or 20A, with matching amperage GFI Breakers and GFI Sockets. I prefer this method because again, the socket will usually trip before the breaker, and I can test the breaker to ensure it is working properly. I've had too many instances where the non-GFI breakers didn't trip after a GFI socket failed to trip. If a GFI socket trips, it doesn't affect the whole line. If a GFI breaker does, well of course it will open the lines circuit.
