remove all crossings alltogether - they are dangerous.

or network rail could enforce a 20mph speed limit on all unmanned and half barrier crossings, and the signaller could caution all trains using a single yellow signal for the signal that is before the signal which protects the level crossing - this would slow trains down sufficiently to avoid an incident if there was a vehicle on the line - but why should network rail do that when at the end of the day its down to the bloody mindedness and stupidity of people in cars who attempt to cross while a train is coming.

the only way to ensure that stuff like this doesnt keep happening is to remove all crossings and replace them with flyovers/bridges or underpasses - i know it isnt exactley the best economic option, but its the only option.