I agree OP, I feel massively unsafe in tube and train stations at night (I live in London). You have that contact machine, but it would be no good during an assault. Maybe afterwards. I have been deliberately followed through Blackfriars train station and then onto the train by a guy who was an old neighbour of mine whose name I didn't even know, recently out of prison and I assumed totally off his head on drugs and recognised me as I was walking through the station by chance. Just my luck to be there at that time. There was absolutely no staff around, and he kept threatening to abduct me and talking about disgusting things he would like to do and he was on edge, vacillating between anger and sexual innuendo whilst pushing himself against me and forcibly grabbing my hand and rubbing his hands down my thigh. No one but another couple of women and a couple at the far end of the station platform and I couldn't use my phone. I had to talk fast to get him to allow me off the train and had to pretend to act naturally and laugh through the fear.
Had to not get off at my home station, as it is dead at night. I quickly calculated that I would be very vulnerable getting off at my station which is pitch dark and literally has a mirror on the wall in the corner tunnel as you go up the steps, not even a camera.
In the end I got off at the station before, which is directly connected to the high street which is really busy. Full of clubbers coming home etc I knew I could have a greater chance of disappearing. Lied and said I was going to my partners and he was waiting for me at the platform.
There were still no staff at that station although there were quite a few people and a couple months later a girl was abducted outside that same busy station, dragged to the small green nearby and raped.
I have also been taken advantage of on a train packed with Rugby fans, with a guy deliberately rubbing his crotch against me, again with little staff at the end station to even report anything to. I don't know that I would have anyway, because I knew it I couldn't prove it.
Women's safety isn't a priority under any government it seems. I support more staff being present on the railways and stations. And on trains, and busses for that matter.