The government's initial response to the welfare expert advisory group's 200-page report is "pathetic", National says, with interest groups and the Green Party also saying more needs to be done.
The overhaul of the welfare system was promised as part of Labour's confidence and supply deal with the Green Party.
The 11-member group appointed in May last year said too many people were leading desperate lives with seriously inadequate incomes.
Chair Cindy Kiro - a former Children's Commissioner - said that's not healthy or sustainable and change was needed.
"That feels pretty urgent for the people who were there but at the same time you have to make decisions and priorities. And if we can look for ways to actually improve experiences and that they get proper entitlement then that's an improvement and I'm keen to see that happen."
The government has said it would start by implementing two of the group's 42 recommendations, with Social Development Minister Carmel Sepuloni saying major change would take years.
National's social development spokesperson Louise Upston said Labour voters should be underwhelmed.
She said the government's response was another example of it not delivering in its 'year of delivery'.
"Labour have talked up a big game in terms of welfare reform and to have picked up two - only two - of the recommendations is quite frankly pathetic.
"One of them - the removal of [the sole parent sanction] - they were originally going to be doing that in December 2017, so it's old news anyway."
Ms Upston said National disagreed with the bulk of the report, including the proposal to scrap the sole parent sanction.
"I don't think the system is broken. It definitely doesn't work for those with the most complex needs, but I don't believe it needs a complete overhaul," she said.
"This is another case of the Greens being promised action in their coalition agreement and receiving nothing when it comes to delivering on that agreement."
Green Party co-leader Marama Davidson said the government was on the right track, but acknowledged that struggling families had been waiting a long time for change.
"I know that for families it's far too late for too many families. I know that there are children who have missed out on things, on living with dignity for over 30 years of successive governments not having a good enough system. I know this is urgent. Greens are clear this is urgent. We want to work with our partners to fix this."
Auckland Action Against Poverty coordinator Ricardo Menendez-March said the government should be moving urgently to remove the sanction on solo parents who do not identify the other parent - something Labour committed to doing during the 2017 election campaign.
"For us to have to wait for most of the term for a decision and now pretty much until the end of the term for it to come into place is disappointing. We think the government is not acting with enough urgency on poverty."
The government has also held off implementing the expert advisory group's recommendation to immediately increase benefit levels by up to 47 percent.
Mr Menendez-March said that would have been a simple way to ease the burden on many struggling families.
"Increasing the core benefit levels and ending all sanctions is one of things they could have done this Wellbeing budget to make a real tangible effect ... so far we're getting more rhetoric than action."
However, Ms Sepuloni said the government could not implement all of the group's recommendations at once and needed time to work through further changes.
"What the report points out, despite saying that there are areas that are urgent and need to be addressed immediately, is that there are complexities in the system and there are interactions that occur across the welfare system that need to be taken into consideration so we have to do it carefully to make sure we get it right."