Navigating in the LoE isn't always quite as easy as has been suggested. Many times I had the entertaining experience
of traversing it, one way or the other, in pretty marginal weather conditions. Some of the prominent navigation features weren't quite so prominent, though I confess that most of those problems evaporated when strobe lighting was installed at various points.
But, when the weather is at VFR minimums, there's a very real chance that you'll be in the same general vicinity as another aircraft. I found that I was seldom the only one using the LoE. It's a lot harder to see another aircraft when you're paddling around in minimum weather conditions.
However, even on a good day, as has been mentioned, it is sometimes very difficult to see another aircraft at or close to your altitude when there's so much background suburban clutter. I think there's a very real reason to use the radio to broadcast entry to the LoE. Perhaps more especially because of the many ultralights that use the same airspace.
So,
CJ, at the risk of upsetting the ultralight community, I must ask why they think they're impervious to a near miss, or worse? There can be a LOT of traffic in the LoE at any given time and my past experience tells me that its well nigh impossible to spot all of them.