I have been working on a new rail design to use in my base. The circle method, which I used previously when trains were still confusing, isn't good enough nowadays.
So, this is the design that I have come up with: This is just a section of the track, which would run with the "one train two cargo wagon" design with an outpost in the middle. The system runs clockwise, and has enough space between the rails for roboports. I'm having trouble trying to come up with a better design for the turning circle at the end (on the left hand side), which is rather large.
Please note that the stations on the left and right hand sides are just for testing, and that this would be connected on the right side to a large main station capable of supporting 5+ trains.
Can anyone tell me if there is a more efficient way of placing the signals, and if there is a way for trains to get blockaded with this design?
Thank you!

P.S. Instead of the double track layout, should I just use the double headed trains on one track with passing points method?
EDIT: I have added in the chain signal on the above picture and added more stuff below. Thank you all for your input!
Here is a junction I've created: Can someone please tell me how to make it so that the two trains may pass at the same time? (The one on the left is going up, and the one in the top is going right)
The picture again but without the trains so that it's easier to see the signals. The stations are just for testing... I was wondering if making a quadruple junction is just the same thing but flipped, is this true?