vanHorck,
Bookworm has it spot on. All your reasons are good, but not related to the second engine.
For me, the biggest advantage of the second engine is actually something which hasn't been mentioned yet - systems redundancy. Every twin that I know of has two vacuum pumps and two alternators.
In a couple of thousand hours of flying, I've never yet experienced an engine failure, and I've only met a couple of people who have. But I have experienced a few alternator failures, and a couple of vacuum pump failures - both of which could cause serious problems if they happened in solid IMC.
Everyone has a different budget, and a different attitude towards risk. For me, the extra cost is not worth it. If I was paying for the flying myself, I'd go for a single every time. The only reason I fly twins is because people pay me to fly them. But that doesn't mean that flying a twin is not right for someone else.
FFF
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