Various Game Boys, Vita, Switch all cramp my hands up. Never had a PSP unfortunately.

It is absolutely the most comfortable gaming device I have ever used. It’s very apparent that Valve spent a significant amount of time to ensure a good experience.

Samsung TVs are dreadful. My soundbar never connects properly and plugging a switch dock into it kills the sound completely. This is their ‘flagship’ model. Sorry I have no solution, but I do emphasise.

A power bank is a good solution. But please check the maximum capacity the airline lets you take on board. Otherwise you’ll lose it!