The lack of ammo is solved with the chainsaw. That’s why they give you puny zombies in every battle. They’re easy to kill for a little health, and it only takes one charge of the chainsaw to fill up on ammo.

Doom rewards you for playing aggressively, much more so that the OG game did. They want you to get right up into the thick of it, not corner peek with your shotgun.

Definitely fair if that’s not your type of game though. It’s plays quite different from the original.