Super Rugby expanded to 18 teams, including sides in Japan and Argentina, this past season but critics in New Zealand felt playing schedules were unfair and that the post-season format was not an accurate reflection of the competition.
Earlier this week, Andy Marinos, the head of tournament organisers SANZAAR, told reporters in Sydney there would be no change to the competition format next season.
NZR's Tew, however, said he had lobbied to change the finals format, where each of the four conference winners -- one each in New Zealand and Australia and two from South Africa -- are given home advantage throughout the post-season.
"We couldn't get agreement from Australia and South Africa," Tew told a conference call with New Zealand media on Friday. "We've tried and haven't completely given up but it's unlikely we'll get any substantial change in the finals format next year.
"If there are any changes for 2018, then that gives another chance to have that debate.
"We think it makes much more sense to have a straight top eight. It makes it a lot easier for the fans. They can almost disregard the complications of the conferences and just look at the log and say 'is my team in the top eight'."
New Zealand sides occupied four of the eight playoffs spots this season. The Otago Highlanders, who finished third on total point, however were ranked fifth according to the format.
The Waikato Chiefs and Canterbury Crusaders also finished with more points than the Australian conference-winning ACT Brumbies, who had the seventh highest points total.
The fourth-ranked Brumbies hosted the Highlanders in the first round of the playoffs and Tew said his organisation felt a table based solely on total points would have been simpler.
"We think it would've produced a fairer finals result this year but our partners think it was an aberration and we won't have four teams in the finals again which is fine," Tew said.
"They don't want a change and you've got to have agreement in SANZAAR... that's the beauty of a joint venture."
(Reporting by Greg Stutchbury; Editing by John O'Brien)
