Ian,
You are correct, you cannot get the driver to balloon in JNPG. This was by design because the devs felt that most players would complain if they couldn't get the extra distance on their drives (since that is what they were accustomed to from earlier golf games). Your posts prove them correct. For the shorter irons the ballooning effect is less pronounced, just as it is in real golf.
I'm curious, but what makes you think you should be able to an extra 20 yards of carry from a 3W in the game as it is now? If you are equating an extra 10% in power level with an extra 10% in distance then you are mistaken as there is no 1:1 relationship between power percentage and distance in JNPG. Since I'm away from home I can't test but I'm pretty sure you can currently get a few more yards carry before the ballooning effect takes over and robs you of distance. Perhaps try hitting at 105% instead of 110. And once the different shafts/balls are introduced you may very well be able to get your extra 20 yards.
As to trajectory adjustment you could be right. I've found that to keep it really low after making the adjustment down I need to hit a lower lofted club with less power.
As to carry/roll between swing styles I don't perceive that to be a disadvantage (and I play RTS-M). To me it is equivalent to the differences one would see between different types of equipment in real life. I would expect to get a few more yards out of a $500.00 driver than I would out of a $100.00 driver. It's just a matter of perspective.
I believe Daz was referring to real life. In JNPG if the tempo of the swing (which has nothing to do with the speed of the swing) is correct the ball with still go straight. We even see that in real life - i.e. Ernie Ells or Fred Couples - a relaxed, easy swing that still goes straight and long.
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