FLI,
No, I think it is generally incorrect to assume that power margin is the way to assure engine failure reliability. Those military engines I note are used in awful environments by Army pilots and mechanics, and the stats are what they are, anyway. The way to assure flight safety is to fix the cause of accidents, FLI, not to add more engine power, but you miss all that, and fail to even consider it.
I note that the numbers don't move you at all, you gloss over the proven experience that there are about 9999 more ways to have an accident than an engine failure in a critical exposure window, ways that get us every day, in spite of the exposure windows we have.
You seem upset about all this, and blame lots of people for your plight. You have choices. Carefully note the cost to operate, the payload, range and OEI peformance, and buy what you want, of course. When you do find the perfect ground level, zero exposure helicopter, do not be disappointed to find the IFR range is a bit shy, and the costs are equivilent to those of an aircraft that carries a bunch more payload, since you are really buying a given helo, and operating it at 75% of its potential.
And for accident prevention, please buy an EGPWS with that new machine!