Thanks for starting this thread Dan, it's the next big issue for Australian rugby.
Firstly as you imply, it's essential that we don't repeat the mistakes of ARC/NRC incarnations both of which tried to put start-up entities into Sydney and Brisbane and thus broke the important link to the level below. It also meant that the competitions couldn't capitalise on the one thing that can't be bought in a sporting context - the tribalism and support which comes from long-standing clubs and long-standing rivalries.
It's also clear in the Australian context that any code wanting a pro or semi-pro competition needs a significant presence in either Sydney or Melbourne (or both). The AFL and the NFL both realised this with expansion into the other's home turf. Just as important is that AFL and NRL have both also realised that even with expansion, it's fatal to neglect your heartland. Another experience from AFL and NRL is that teenagers who have aspirations of a professional career still have a desire to remain in their home state. Quite a few of the AFL top draft picks from Melbourne end up interstate and they nearly all try to get back to Melbourne when that first contract is over. Same with AFL guys from Perth drafted to the East Coast, they want to play in their home town. At the moment Sydney produces a significant percentage of rugby players but there's only one professional rugby team in a city of almost 4 million people - so a proportion of kids who are good at both league and union have a pathway of 9 NRL clubs or 1 Super Rugby franchise. Rugby is almost pushing these kids to league. (Angus Crichton as just one example)
It's also instructive to look back and see what England and France did when professional rugby arrived in 1996 and look at the path we took as a way of identifying what might work moving forward in Australia. It's also beneficial to look at England and France for two other reasons - firstly rugby isn't the dominant winter sport in either country, and secondly rugby isn't evenly spread in either country but has a heartland in parts of each nation where more teams are located than bare population numbers would suggest.
In both cases, previously amateur clubs were given the opportunity to professionalise their operations and become elite professional set-ups. There was no move to create new entities devoid of history or emotional connections with a local fan base. Some clubs took up the professional challenge and have progressed in the 25 years on professional rugby, while others chose to remain amateur or semi-pro in lower divisions. Many of these clubs draw from a population of fewer people than some Sydney and Brisbane clubs (see below). There's also a geographical bias towards the rugby heartland areas so that the areas which produce more rugby players and have more rugby fans have more teams.
English Premiership Rugby (12 clubs)
South West England (4 clubs)
Bristol (pop 467,000)
Bath (pop 88,000)
Gloucester (pop 129,000)
Exeter (pop 131,000)
Midlands (4 clubs)
Northampton (pop 215,000)
Worcester (pop 101,000)
Leicester (pop 357,000)
Wasps (Coventry - pop 325,000)
North East (1 club)
Newcastle (pop 302,000)
North West (1 club)
Sale (pop 55,000)
London (2 clubs)
Saracens
London Irish
French Top 14 (14 clubs)
South West (7 clubs)
La Rochelle (pop 75,000)
Perpignan (pop 121,000)
Toulouse (pop 471,000)
Brive (pop 46,000)
Pau (pop 76,000)
Biarritz (pop 24,500)
Bordeaux-Begles (pop 257,000)
South and South East (4 clubs)
Lyon (pop 518,000)
Montpellier (pop 240,000)
Castres (pop 41,700)
Toulon (pop 176,500)
Paris (2 clubs)
Stade Francais
Racing 92
Central (1 club)
Clermont-Ferrand (pop 141,000)
On occasion Grenoble (from the east of the country in the Alps - pop 158,000) are also in the competition under the French promotion/relegation system)
So in taking an approach where any national rugby competition takes advantage of historical clubs and the associated would be my strong preference and I'd suggest it's the only option with a realistic chance of success. This should be coupled with a concentration in the heartland of the game where there are the most fans and players.
Any competition should have 10 -12 teams - and I assume that it would be uncontroversial to have a Melbourne team and a Perth team in the expansion states (to occupy similar roles to Melbourne Storm RL and Brisbane Lions AFL).
Then there becomes a whole range of different permeations which could work depending on who would want to participate and under what terms.
At this point I would note that Eastwood have recently sold their ground at Eastwood in the Ryde part of their area and are going to build an elite playing and training complex at Dural in the growing hills district of their area. They may be now the richest rugby club in Australia and well set up to play in a national competition should they want to do so. Combined population of Hills Shire and Ryde is 230,000.
Sydney University have significant resources and the ability to run an elite rugby programme on campus. I think they would have the resources if they wanted to go there. (They could even link up with Norths and Gordon as the Sydney Waratahs - the Waratahs name would give every other team in the competition a place to focus irrational hatred -this part is tongue in cheek
)
Randwick have always harboured desires to participate as Randwick in a national competition. I don't know if they still do, but I suspect that the baton is still in the knapsack) Population of Randwick City LGA is 156,000, when combined with parts of their area in other LGAs it's over 220,000).
The Manly-Warringah area (Northern Beaches LGA population 275,000) competes as one combined team in every sport except rugby. It has in the past always been their view that they should play as Manly-Warringah in any national competition. This also has important brand recognition through the MW Sea Eagles on a national level and would unite the whole area.
Parramatta/Western Sydney can't be left out. Cumberland Council have just built them a great facility and West Harbour are part of a high performance hub at Concord Oval. The area has a huge population Parramatta, Cumberland and Penrith LGAs have over 750,000 people (before you even get to Blacktown, Liverpool etc which takes the population to almost 2 million), and there are plenty of rugby people. Would need NSWRU or RA support.
In Canberra, I quite like the idea of a Tuggeranong Vikings and a combined Canberra Brumbies as it brings a Canberra derby but I would bow to greater local knowledge on this. At face value it seems something which should at least be examined seriously.
For a 12 team competition, this leaves 3 teams to go in Queensland. Not wanting to offend anyone in Queensland by presuming to say what I think would work best, I'll leave it by saying that it's logical for a 12 team competition to have 3 in Queensland. The truth is I simply don't have the local knowledge of Brisbane rugby to say what would work best.
In terms of when such a competition should run, my very strong view is that it should run parallel to Shute Shield, Brisbane PR etc. Obviously as we still have Super Rugby, then this competition would be semi-pro - which probably isn't a bad way to start.
Just my views or course, but that's what the site is for and I expect criticism - but if you're not being criticised then you probably aren't doing anything worthwhile.
I'm just going out to put my crash helmet on for the incoming.