Listen to the Rain

That's part of the other reason I want a scalable system. Exalted is pretty good in one respect, because it's just (Strength/Dexterity) + Martial Arts vs (Strength/Dexterity) + Martial Arts and the actual rules take up only a couple paragraphs, but it's also really bad because the person who's grappled has all of their combat options narrow into A) get unclinched or B) die.

Like you say, the ideal is for it to be just one more thing that affects combat, like unstable footing, pools of flammable liquid, and so on, and people who are good enough at grappling can ignore other people's puny attempts to restrain them if they want, the same way agile-enough people can fight on unstable footing or whatever.

More specifically on the subject of your comment, is there an RPG you'd consider to have good grappling rules that match your thoughts? The most I can usually say for RPG grappling rules is "They're acceptable" or "They're not bad, except-"