I believe this proposal can also solve the problem of players missing the lie with their plant foot. I had previously proposed enlarging the "stance zone" to a 60 cm diameter circle. This would be much easier to hit on a run-up, but might be too large a leeway when you are close to the basket, and you could get an advantage by stretching an extra 30 cm to the side to get around an obstacle. If we use the 30 m mark for a "no follow through" line, we could also use it for a "no 60 cm stance zone" line. Beyond that line, the player would take a stance on the line of play, as we do (or vaguely attempt to do) now.
So are you proposing that distances greater than 30m you can use this 60cm circle, but then inside 30m, stance is on LOP? So if a player's disc is 35m away from the basket and behind a bush, now that player is given an additional 30cm to the left or right of the LOP? Why would you eliminate the concept of the LOP? You should throw behind your disc, that's your lie. And so now the rule changes within 30m, you must be on the LOP, which goes back to distinguishing if you are +/-30m outside. I can just see it, player's disc lands behind a bush, and declares he is outside the 30m, so therefore he gets an extra 30cm to the L/R of the LOP to get around that obstacle. I think sometimes it's just easier to keep things simple. The LOP in all circumstances, whether it's a fairway drive or putt is easier to ascertain from another group member's view if the player has committed a stance violation.