To be fair, apart from the one premiership in 2005, I'd say the Wests Tigers hasn't worked all that well to date. Their club(s) were a shambles for a long time with the Balmain share basically going bust, Their back of house has been disorganised with continual CEO changes and in fighting, their football operations has been terrible (look at how many coaches they have punted, especially with the players having the key say in who stayed/left), and despite being called 'Wests' they have a significant identity problem because they represent distinctly different areas and bounce between 3-4 home grounds (Campbelltown, Leichhardt, ANZ and now Bankwest).
NS/CC already tried the whole amalgamation of areas in the Northern Eagles and whilst this was marred by the NS/Manly power struggle destroying the club, you can't exactly say the split between Gosford and Brookvale helped them. Their on field performance from memory, wasn't exactly dazzling either and I'd argue was a reflection of how bad things were with the back of house.
You hit on a good point about the identity issue with Wests Tigers.
Playing at a jumble of home venues does not help - just as NOT wearing mainly orange jerseys (their biggest point of difference from ALL other NRL teams) does not help. Now Wests pretty much ARE the Wests Tigers (RIP
While spiritually it may have made sense for two ailing foundation teams to join forces, the Magpies 1980s relocation to Campbelltown made it geographically ridiculous. They need to figure out where they fit in Sydney’s map, and fast.
As for the Northern Eagles, in hindsight the split between Gosford & Brookvale was part of the problem. If the animosity between the Bears and Sea-Eagles factions wasn't there, maybe they could have turned out like St George-Illawarra... unfocused, spread between two home grounds, and under-achieving.
I used to think that super-regional teams like the St George-Illawarra Dragons, and a re-booted Northern Eagles-type team (North Sydney/Manly/Central Coast) were the way to go, but now I think a club needs ONE home ground, ONE main base.
Move Dragons to the 'Gong, move Manly or Roosters or whoever to Gosford.
The "Sydney plus a region" experiment has failed. Time to move teams out full-time.
They'll play enough away games in Sydney anyway....