I like that 1917 cast two normal looking actors as the leads

Not only are George McCkay and Dean Charles Chapman relative unknowns, but they look like normal young blokes.

Usually, hollywood either casts A listers or really good looking model looking people (this was the case with Dunkirk, which starred Fionn Whitehead and Harry Styles).

I think this payed off a lot with 1917, because they really did look like everymen. It made the film more immersive and horrifying in a way.