Castle officially started as the first female chief executive of a major football code in Australia on Monday after being appointed to succeed Bill Pulver last month.
Castle inherits an organisation battling for relevancy in a crowded sporting market, with poor performances on the pitch at the highest levels last year exacerbating strife off it.
"There need to be better performances in Super Rugby this year," Castle told reporters in Sydney. "That's the way that builds the platform for what people expect and how they engage with rugby.
"(We want to see) some stability and some moving forward that people can see across ... the performance of the Wallabies, community engagement, making sure we've got some strong commercial programmes in place.
"Those'll be the measures across the sport that people will say, 'what does success look like in the first 12 months?'"
The former Netball New Zealand and Canterbury Bulldogs chief executive faces an uphill battle after a year when the game was ripped apart by infighting over Rugby Australia's cull of the Western Force from Super Rugby.
None of Australia's Super Rugby sides beat a New Zealand team over the course of the season and the ACT Brumbies only qualified for the playoffs by virtue of the convoluted ranking system that has been abandoned.
While the concentration of the player pool from five to four Super Rugby teams could help with results, Castle added she was concerned rival codes were picking off their talented players.
"If we're developing the talent, we want to make sure we keep hold of the best of them in that place where they're playing schoolboy rugby," she said.
"We need to make sure we're capturing those athletes as they move into that semi-professional and professional space.
"That is an important transition - we have lost too many to rugby league over the time, so that is something we'll be looking to make sure we shore up."
Castle's relationship with Wallabies coach Michael Cheika is also likely to come under heavy scrutiny, especially after the national side lurched through an inconsistent 2017.
The Wallabies, despite beating the world champion All Blacks in their final test at home, were also beaten by Scotland twice, which included a record 53-24 thrashing in Edinburgh on their end-of-year tour.
"The relationship between the CEO and the coach is incredibly important," she said, adding that she would meet Cheika on Tuesday.
"It's about making sure that we find an engagement that works really well that we can help each other and work closely together."
(Reporting by Greg Stutchbury in Wellington; Editing by Peter Rutherford)
