Ah, I wasn't making an assumption of left vs right, but looking at the train signal's direction... though, it seems I was mistaken on which way they face for a given light orientation. (I reeeeally can't wait for the devs to pick a stable version so I can get back into this
As for the layout critique, it's a good bit off-topic, but I'll address it for a post.
Roundabouts are your friend, and are the only way to avoid potential deadlock.
Your rails themselves are a pretty good setup for a non-roundabout junction. (The uneven curves irk me, but that's a personal problem
With this kind of junction there's not much room for improving the signals and still maintaining reliability.
Due to the current implementation of Factorio's signals, throughput/non-delay is roughly inverse to the avoidance of deadlock. I would attribute most of this to the fact there's no way to signal a path is clear, without also signalling that a train can stop at that signal's location. (e.g. there's no signal that only tells when one side of a block is clear)
Generally speaking, I avoid placing any signals where a train that stops at that signal would be in the way of other trains.
By only having one train in a junction at a time, you strongly avoid any situations that could cause a deadlock. Limiting the junction to one at a time will undoubtedly cause delays for bypassing trains however.
Personally, I'll sacrifice a reasonable level of throughput for never having to look at the junction ever again.
For reference, the "single train in junction" signal setup I refer to is a single signal at each entrance to the junction, and a single signal on each exit at [the maximum train length] away from the junction. Distance from junction depends on how large a train you're ever going to run on that line.
Only real improvement to this would be a roundabout, so it's not a bad layout for what it is.