Yeah, no, IMO anyway. Those 'problems' are as gossamer in the sunlight, and should prove just as ephemeral. If you don't need your hand held when it comes to the rules, and you either don't have or can properly manage players who constantly hunt for mechanical advantage, you won't have any issues. The answer to free actions and range questions are a pretty easy no. A child pouring sand over a ledge isn't the same as a trained fighter using a targeted dirty trick either, and the differences are obvious.
Notions that occur to the kind of of player that hunts mechanical advantage always sound just like your examples. They all sound very much like pushing your luck and they all sounds faintly ludicrous, as fluff dreamed up in these cases usually does - it always sounds contrived. I can smell that crap like a fart in a car, and my players are either already adults who have better gaming instincts than that, or I can disabuse them pretty quickly of the idea that I want to indulge in that nonsense at all. Not as a matter of control or authority, but out of a genuine aesthetic distaste for that particular flavor of rules indexed wanking.
