How about compromise? We keep most of the suburban grounds as they are and only make a couple adjustments in terms of stadium arrangements. I would have the NRL team up with the A-League and pressure the powers to be to renovate SFS and help turn Parramatta Stadium into a 35,000 seat mini Suncorp Stadium complete with parking and transportation links. I would build a new stadium for Manly in the Northern Beaches area with parking. And I would renovate Redfern/Belmore so that they could a couple regular season matches a year and move the Bulldogs and Rabbitohs to Parramatta Stadium and SFS, respectively. ANZ thus could get a SCG vibe to it, hosting Origin, Grand Finals, doubleheaders, and larger rivalry games.
So I could see a stadium arrangement go something like this:
Bulldogs- 9-10 games @Parramatta, 2-3 games @ Belmore
Cronulla- 12 games at Shark Park
Manly-10 games at new stadium, 2 games @ Brookvale
Souths-9-10 games at SFS, 2-3 games at Redfern
St George-Illawarra-6 games at Wollongong, 6 games at Kogarah
Parramatta-12 games @ Parramatta Stadium
Penrith-10 games at Centerbet Stadium, 2 games at Parramatta Stadium
Roosters-12 games @SFS
Wests Tigers- 4-5 games @Campbelltown, 3-4 games at Leichhardt Oval, and 3-5 games @ANZ/SFS.
I would try to move bigger games to ANZ Stadium and try to market the heck out of them. So this arrangement you would get the best of all possible worlds. With Parramatta and SFS, you would get a modern rectangular stadium and modern facilities. With ANZ, you would get a big game feel. And with the suburban grounds, you would get an atmosphere, history, and tradition.