In theory I agree I think we have similar thoughts, however I'm a realist (it might be my age or having spent a few years in government & the private sector) I personally don't think it would work. For example currently in SES the busiest RCR units get the latest gear & its not just based on cost, the older equipment is serviced and issued to the less exposed rural units and then to metro for USAR.
The SMAG (subject matter advisory group for RCR made up of vollies & payed staff) work out what is the best in current equipment, techniques & training and it is rolled out. The system is not perfect but it works.
Under your system rescue would compete with structural fire, wild fire, hazmat etc for dollars. The latest and greatest gear would end up with high profile metro units/ brigades. High risk rural units would be second (maybe)& others third. And then the competition would be between $1.2 million comms trucks, hook trucks (sorry couldn't resist), sky cranes, weird projects that keep saying the same thing etc. Rural SES units would fold as there would be nothing for them to do, RCR is our bread and butter! Then when the big one happens(What ever that may be) you won't have the people- it would be the same as pre SES - fire services can't cope etc(THATS WHY WE WERE FORMED REMEMBER?). Then there is the training = if you find it hard to get people to keep current in BA & burn over drills, how the filtered are they going to stay current in RCR? (We do a refresher every three years regardless)
Finally if you think SES members would come madly rushing to the fire services, then you are wrong. In SES we are fairly independent & we like it that way I for one can't handle the by the numbers system that CFS uses or the group structure that the fire services have. I like our flatter structure and couldn't handle your system.
So instead my vision of the future is this:- combined fire services both payed & vollie doing fire in all parts of the state & rescue at full time stations & strategically located rescue units across the state wearing orange & called State Emergency Service. Both services managed by SAFECOM, SES properly resourced could finally to be able to carry out its daily role of rescue & also its civil defence role properly in all units.
In areas where numbers are low of course a combined unit makes sense fire side trained by fire & the rescue side trained by SES. (Onkaparinga, Blanchtown,Bordertown?)
Duplication - in areas where SES operates then the fire services should not have rescue equipment, only their combitools to break into buildings on fire. If they have RCR gear then they shouldn't that is duplication.
As far as your Hazmat question - after watching a Hazmat team set up and do its thing the Golden hour doesn't mean much so its not relevent, fuels of course are managed differently & we have the gear that can operate in that environment.
So I guess the real question is should SES take over ALL rescue in areas not under the control of full time fire crews. Now there is something to think about.
cheers