Os, I'll be honest and say I prefer a stick swing compared to 3-Click as for me, it feels more immersive for a golf game - I don't want to only be timing a button press to swing a club, that bores me.
You are correct however in that 3C is more difficult and provides better dispersion as well as more competitiveness taking dodgy, straight-lining controllers out the game (ignoring possible hacks of course). There is 1 major reason for this - with 3C, you are timing your click to 2 thin lines which takes skill whereas TGC's swing is to hit inside a zone rather than a line. You mistime the click for the bottom line even by a little, you get a bigger dispersion whereas TGC you can be off-centre of the area yet inside it and you'll still hit straight. That with the overswing being present in 3C really adds to the difficulty. HB tried to make the swing more difficult by adding slight dispersion within the zones if not hit dead centre but it's not much.
The trick would be to somehow formulate a stick swing to mimic the 3C function providing the same outcomes as 3C - BS for power (bar increasing in 3C including being able to go passed the 100% mark), and then something to mimic hitting the button for straightness as the DS swing plane just does not do it. Maybe the swing plane can be type of shot (draw/fade/straight) and as you DS you have to time a button press to as you hit the ball (being the bottom line to aim for in 3C). Hit the button before the ball would equate to a pull (left of the line in 3C) after and would equate to a push (right of the line in 3C). You pull back further than 100% and the DS animation would be a lot faster and therefore harder to time your button press as you connect with the ball. Maybe something like that or similar perhaps. I dunno. Power could also be tied to how fast your DS is like I've seen in the Tiger/Rory games. Follow through too fast and you add power to what you've already set on your BS, too slow and it knocks some off - would make it more reliant on good pace and maybe have the animation follow how fast you are pushing forward so timing your button press is more difficult.
In any case, the stick swing does need to made more difficult to perfect and dispersion needs to be upped so it's not just a game of math. Like your videos and like the guys above, it's got me thinking of reinstalling Rory to give it a go - looks so darn good yet I know after 1 round I'll not play it again as I do prefer TGC.