We have developed a new system that uses train track direction and no-stopping zones instead of your block and chain signals. The motivation was to make train network building easier but not to compromise on what can be achieved in terms of rail network complexity.
In short, instead of chain signals ensuring that trains can pass through intersections without blocking them, in our system, intersections are marked as "no-stopping-zones" and train will only enter a no-stopping zone if it can reserve enough track along its path to fully clear it. This is even better than chain signals, because it takes into account the train length.
We even support bi-directional tracks that allow for terminus stations, or sidings on bi-directional routes, all while guaranteeing that no trains will get stuck (when configured correctly). These use "exclusive zones" that restrict only one train to ever occupy bi-directional sections.
This has taken us nearly a year and while the system is not perfect, our early testers love it. I am not claiming that you won’t be able to get trains stuck with this system, but I do think that the kind of issues and their solutions are easier to understand and resolve than with chain signals. Only time will tell though. If you are interested in more details, see our blog post: https://www.captain-of-industry.com/post/cd-46
I’d love to hear your thoughts!