some find the weight of the nose with the power idle too heavy, and so the addition of power is needed to assist.
I see it differently, if some find the pitch forces of a 172 too heavy, that's an extra reason for power idle practice in it (or physical strength building)! Wait until they fly the much heavier C 206! Despite its ubiquitous presence in GA, a 172 is generally there to enable training, so a pilot has the foundation of skill (and muscle, I guess) to go on to other types. There is no characteristic of a 172, which other GA types would not have to a greater extreme in one way or another - certainly pitch control forces. Sure, a student can use the 172 to build skills, but when they are competent in it, they should be able to fly it with common skill and precision power idle - from cruise flight, to a gentle touchdown, including the use of slipping and flaps as appropriate to the approach. Power should be used as a performance aid, but not a handling aid.
A long time ago, I had some flight testing to do on two different Piper Navajo's. I'd never flown a Navajo before, and no one was available to check me out, so I read the flight manual, and checked myself out in it. I did find, as you'll agree, that carrying power on final made it "nicer" to land, so for the first few landings, I was nicely kissing it on the runway using that technique. But that was my entry point with that type. By the time I was done, I was content to approach power idle.
Off topic, one of the Navajos was this one:
As an aside, for most retractables, you could be setting yourself up for a nasty surprise in the flare (if even there), if you fly powered final approaches, as it is the movement of the throttle(s) to the idle position which causes the gear warning horn if you've forgotten to extend it - It'll be too late in the flare! I realized this for myself (safely!) during my early Navajo flying, so even though I still cheated my early landings by carrying power across the fence, during my mid final landing gear check, I would close the throttles to listen for the horn.