Hotbox and Draging Equipment Detectors have been in preliminary discussions for CTC, but while TD3 uses this feature all over the place, we're thinking about localizing the detectors, e.g. in a block or between blocks, so that you can place where you want the detectors to be . Note, the "HB" and "DE" markers are for show only , there is no functionality behind them.
Random train issues have not been thought of yet, however this would be similar to how TD3 handles HB/DE/what not handles these things. Emergency brake is already part of CTC, although you won't see it too often. Slow downs because of some issues is not (yet)
These things may also impact the communication between the driver and the dispatcher. After all, you like to know what is going on, and I think it is common courtesy (or protocol) for the driver to call you about any problems.
Switch and signal failures have been thought of - and some pieces are already there (though dormant). The deterioration will likely be handled like block deterioration - e.g. surviving sessions etc.
Switch failure may be addressed by the train crew - remove a blocking tree branch, manually throw that switch), that would be also subject to some communications.