Trailing-point half-crossovers like ours are inherently safer - a mis-thrown switch doesn't have the possibility of leading to a head-on collision between vehicles, like leading-point half-crossovers do.
There's no need to have full-full crossovers, either, unless you want to reverse-run for a short section of a route due to platform or track maintenance in a short section and have a pinch (not an issue when your headways are as big as ours, but that's another discussion...). Our system was never designed with that capability in mind (otherwise there would be full crossovers at much more frequent intervals).
The trailing-point setup we have will be just fine for ion. Simple, cheap, and effective - the motto of the entire system, really, and an excellent model for others to follow.
There's no need to have full-full crossovers, either, unless you want to reverse-run for a short section of a route due to platform or track maintenance in a short section and have a pinch (not an issue when your headways are as big as ours, but that's another discussion...). Our system was never designed with that capability in mind (otherwise there would be full crossovers at much more frequent intervals).
The trailing-point setup we have will be just fine for ion. Simple, cheap, and effective - the motto of the entire system, really, and an excellent model for others to follow.