Wolfenstein, Doom, Quake, and Marathon were all revolutionary for their times as well. Each had their own unique implementations.

Wolfenstein and Doom speak for themselves, couple of the first FPSes in existance, Doom even brought about ESRB, Quake brought a new standard of graphics and sparked the arena-style deathmatch fest that went on durring those years, and Marathon (1 at least) brought in features like reloading and radars as well as some pretty impressive visuals.

Every game nowadays having that "recharging health" does get kind of annoying though tbh... health packs have always been a huge part of FPSes until Halo came along.