To put on my Professor Arthur Hat for a moment and score some petty political points; much as Labour's every reply to the Scottish Government's insistence on more powers/independence is greeted with cries of "use the powers you already have first", I'd say Edinburgh could already be doing quite a bit more to deal with parking violations under the legal framework we already have, so perhaps begin there. Those items would be fine additions to the arsenal, but of little use unless actually used in practice.
As usual though, the real problem is they lack ambition - where's the demand for a means testing system, not to reduce fines for "the poor"(who can afford to own and run a motor), but to radically increase them for the rich? Where's the demand for powers to enable citizen enforcement like they have in New York, where anybody can download an app that lets them gather and submit evidence of engine idling and receive a cash bounty for every fine the city gets paid? And the similar apps that are starting to come up in some US cities for parking violations? Where's the demand that the multiple gaping "I'll just be five minutes gov" exceptions & loopholes in existing legislation are closed?
It's been made quite clear by Op Snap and the virulent reaction to ANPR cameras down south that it isn't laws themselves that prevent road violence, but how likely drivers feel they are to be caught violating them - the only way we're ever really going to tackle blights like pavement parking and vehicle idling is to turn every mobile phone into a potential enforcement camera and make drivers *very* aware of that reality.