Reading through your descriptions it sounds like some are modelled correctly, and some aren't. i.e.

If you "switch off ALL the cross-feeds valves AND the boost pumps",  the engines are designed to continue to run just like in a real C-130 through gravity feed.  Only if you climb quickly with the boost pumps off would you expect to see come possible engine fluctuation that could lead to a compressor stall.  If I remember right the only way to stop fuel to the engines if pull the fire handle, or place the condition lever feather.  I believe in both cases it's closes the fuel value.

On the hydralics, some of the items such as the brakes would have one brake application with the pumps were turned off.  The others shouldn't operate excect for the flight controls.  There is another switch for those, and even if you turned that off you would still be able to fly the plane because the C130 flight control are cable driven.  It takes a lot more muscle, but in a flight sim you would feel it anyways.

The suction boost pumps assist the hydraulic system, but you would only see a temporary large drop in pressure, while operating the landing gear or flaps.  Otherwise it should have an effect.

Doesn't sound like the electricals right, though there are a lot of electrically switch you have to turn off.  Each generator, inverters, and even then you have some things hot wired to the battery.  i.e. one of the radios, of course if you turn that off. It should be off.

Anyway, there are a lot of redundant systems on the Herc.  It's a fantactic plane to fly.  Engineers feel free to chime in, I really stretching my memory here. 

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The moderator has a good point. A tremendous amount of work goes into replicating the C130, and nothing is duplicated exactly.  They do what is possible, but even that has to have it's limits or it would never be ready for release.  Besides, not even multi-million flight simulator can do that. 

From my point of view, this would be an impossible feat anyways because no two C130 are that same.  Each model/version (A, B, E, H, J, and whatever other versions that out there) has similar systems, each aircraft gets modified on the assembly line. Before they come off the shelf they are modified for the place they are going, the mission that they will be performing, etc.  Once they get there, the base modifies them even more, in addition each year comes more modifications.  As they are transfered to a different base, region, area of the world more mods take place, and so on.  It never ends, thus I'd be surprized if they are any two C130s that are exactly the same.  I would imagine that this applies to  commercial C130s as well.