I'm not convinced Stuart is a great halves coach. At the Roosters and then the Sharks his record with a number seven saw Soward and Finch at other clubs and little luck with the Sharks halves. Time will tell though.
Unfortunately I share your sentiments on Stuart and halves! Cronulla were always searching for that elusive halfback
However it's worth noting that Finch actually played well under Ricky, I wonder how much of the problem is the difficulty in actually finding a bloke who can play number 7 in the top grade. Worth noting that in any given season there are at least half the clubs in the comp who don't have a top grade quality 7.
This season:
Bulldogs
Rabbitohs? (time will tell, but seems the young bloke is just a kicker)
Sharks (although Carney compensates from 6)
Raiders
Broncos
Tigers
Knights
Dragons
Panthers (I don't want to argue about the merits of Walsh - happy to be wrong here if others disagree)
Some of those teams have young halfbacks who COULD be good in the future, but those blokes are year 1 or 2 and Sandow is simply them 4 years down the track IF they pan out properly and don't get that massive slump that happens to so many young halfbacks.
Anyway, back to the point, hopefully it was lack of opportunity with Ricky and halves coaching, and not lack of ability. But I guess we'll see.