I've crossed Europe and Russia by train while receiving emails and calls from work (from Brazil) during 50 days and the only machine I had was a 2017 10'5 iPad Pro. I've ditched the laptop because of how light it was and also the fact that it could connect to cellular networks with a SIM card. So I had a browser, Slack, Fortinet VPN, ProtonMail client, Shelly SSH client, Textastic and Working copy (git), TeamViewer, RealVNC and the Microsoft RDP client along with some network debugging tools (ping, whois, traceroute etc). I didn't needed any more than that.
Negative points about this experience:
My keyboard (logicool) didn't had an escape key having a home button on the place of esc. I consider this beyond retarded. Also for some retarded reason cellular functions like sending and receiving SMS is disabled even while using a SIM card.