Wrasslin Owlbears

Grappling is fun. Jump on the dude and pull 'em to the ground, strangle the life out. Just like Conan! RAAWWGGHH BODYSLAAAMMM!! Like everything else in life people try to overly complicate grappling rules. I like my gameplay simple and decisive. If you put yourself at risk to accomplish a goal your success has to be worth the danger. I try to encourage players to do things other than just say "I stab his face". You gotta make the mechanics just as simple as attack rolls. Saves are good for everything.

A strength check is enough--how does your strength compare to their strength? Maybe if the other guy is big enough they could get a size bonus, but who really cares? How much fun would it be for the halfling with 18 strength to strangle an ogre to death? We know from the fiction that he couldn't choke out a black dragon but I'm willing to be lenient in certain cases for rule of cool.

If they want to strangle an unsuspecting victim unconscious they'll probably automatically succeed if they pass the check, especially if they're using a garrote. Regular combat is too granular to go straight to auto-shotting dudes while grappling, so mostly its about restraining a foe, and yourself at the same time while both combatants struggle for supremacy. If you wanna try to throttle them after grappling they take d4 damage on proceeding turns. You can't grapple someone and stab them with something bigger than a dagger at the same time.

A PC with a martial arts background could probably do more with hand-to-hand combat than others. If a Tanner cum lvl 1 fighter wants to throw sick high kicks he'll just  fall on his face.

The danger is here: If you fail your save it puts you at a disadvantage. Oftentimes this means the grappler becomes the grapplee, or gets knock prone, or thrown off a cliff, or gets sucker punched in the tussle. Depending on what system I'm running getting attacked while defenseless could mean a bonus damage die, damage taking the next die size up, or jumping straight to critical damage. If two PCs are holding a monster while the third stabs it in the face the fight is probably over. This goes both ways: monters can and do use the most of the grappling mechanics.

Wizlock--magically bind someone's wrists together after touching them. Can be broken with a strength check Vs caster's Int.

Pile-d-d-driver--after grappling an opponent bodyslam them on the following turn. 1HD monsters are instantly killed. All others take d12 damage and are knocked prone for d4 turns.