Manawatu's chief executive Hayden Smith says a return to promotion-relegation games in the 12-team provincial championship would be a step back.
He says promotion-relegation should be automatic as it is in English football.
And Smith claims proposed changes to Ranfurly Shield rules would also disadvantage smaller unions.
The NZRU's suggesting that shield holders can defend it at home for only four games and all matches after that would be challenges, other than championship playoffs and finals.
Smith says with five or six home games if a team like Manawatu won the shield early and defended it four times at home its next challenge could be in Auckland, which wouldn't be fair.
However the Auckland coach Pat Lam, whose team's pre-season included two away Shield games against Poverty Bay and North Otago, is all in favour of road Shield defences.
Auckland defend the Shield against Taranaki at Eden Park on Sunday.
Two provincial unions are to be cut from the national championship but who they are won't be known til next Tuesday, after more discussion with all unions on the NZRU draft report.