This is why I adore Savage Worlds system. For most creatures in the world (extras) it takes one good hit to get rid of them. The not-so-good hits make them Shaken - hurt enough to be out of the fight for some time. Simple, pretty realistic and a great base for narrative description.
I think this simple combat narration can add a lot of flavor to games. Recently, I stumbled upon a deck of cards being kickstarted just for that - you should check out the Combat Description Cards for Storytellers and GMs.
Before I was aware of the Combat Description Cards, I was using critical hit tables from Warhammer Fantasy Roleplay. WFRP has a hit point system, but the tables can be used to represent both Shaken, Wounded and Incapacitated in Savage Worlds. I am using the tables and sometimes the webapp from Winds of Chaos.
Those charts are pretty gory and grim, often adding extra rules (test modifiers, weapon dropping etc). Use those extra rules if you are after more grim and gritty experience, or skip them and use only the descriptions for more heroic feel. Simply use low numbers for Shaken (1-5), mid for Wounds (6-10) and anything above 10 for death.
I am also toying with an idea for creating charts or cards like that exclusively for Savage Worlds. Just some good narration bits for Shaken, Wounded and Incapacitated. With different sources giving different effects.