I've got an expensive Heinzmann bike, and it's not insured. (My household insurers wouldn't take it on, I'm too lazy to shop around for different insurers, and when I've looked at bike-specific insurance, it seems too expensive, for limited cover.)
At this time of year, I bus more than cycle. But in summer I usually bike to work, and my bike spends the day in one of many bike racks around this large hospital, where I can see it from my office window.
I use a good-quality dee-lock round the front wheel, frame and bike stand. This "fills" the lock pretty well, so it would be difficult to get a tool (bottle jack or whatever) inside it to force it. Then I use a cable lock through back wheel, frame and bike stand. So they'd need two different tools to get it free. The battery is in a standard rear pannier, not the special fitted Heinzmann one, so it's a bit disguised, and there's another cable lock securing the battery to the bike.
I occasionally park it elsewhere for shopping etc, still double-locked. There are some parts of town with a "bad" reputation, where I probably wouldn't take it. But early morning strikes me as safer than evening. Do yobs get up early? At home, it lives in the flat with me. I aim to make my bike a bit harder to steal than the next bike in the row. If that ever lets me down and I lose it, well, that's life.
Mary