Sweeper

Ragdoll physics, and by extension the delayed respawn, give the player the feeling that they made a mistake and lets them process it. The ragdoll is a consequence of their failure, it makes the player feel some shame for their mistake. I think making the sweeper arm have a variant that cannot be jumped over would add the challenge of timing the player's movements just right, even more so than with the thin, knife sweeper. The first obstacle ususally is a foreshadowing of what kinds of challenges a player will face during their experience: parkour, puzzles, time trials, etc. It should tell the player how hard the game will be, though the significance of challenge ramp-up can affect that perception.