Unfortunately because I'm in NZ, mobile data is super expensive, so I only get 2.25GB/month. Turns out that's adequate for 1 hour of train per day (30min each way), but I have to be a bit careful. I use https://www.tripmode.ch/ to limit my usage somewhat.
The keyboard on my MBP is absolutely awful, and if I use it for more than about 20 minutes I get sore fingers. The backspace key requires about a tonne of force to register a delete. So I use a Coolermaster MasterKeys Pro S. It's a bit awkward using it on the train, but I usually do anyway because my fingers kill me otherwise. It helps if I have a spare seat next to me.
Working on the train shaves an hour off my office day, so I get more time with my daughter. I can work from home a couple days a week, but I prefer to go in to the office when possible since I find I focus better at the office.