Newmarket architect and group spokesman Barry Copeland said instead of extending the wharves, the group favoured the second option which was transforming existing land on Wynyard Point into the syndicate bases.
"This would not only be more cost effective, but would also be a productive use for the land, and continue the regeneration of the area into a more usable urban space" Copeland.
"We have an incredible opportunity to build with the future in mind, to keep the harbour for the next generations, and open up access to more of our iconic waterfront for not only for Aucklanders, but for the hundreds of thousands of tourists that flock to this great city."
In the letter signed by a number of leading architects and designers including New Zealand Institute of Architects Auckland branch chairman Tony van Raat, Richard Harris, Julie Stout, Pip Cheshire and Craig Moller, the group said the Wynyard Point option would be a great opportunity to open up industrial waterfront land for further urban development in the future.
"We strongly recommend and support using existing waterfront land on Wynyard Point to house the America's Cup syndicate bases. In addition to saving vast sums of public money, it would have the added bonus of bringing forward much-needed progress on the continued development of our iconic waterfront and open up access for the vast numbers of Aucklanders and tourists who relish being close to Auckland's great harbour," the letter said.
Lobby group Stop Stealing Our Harbour is also opposing the Wynyard Basin plan because it would see a "shed farm" block its views.
Auckland Mayor Phil Goff told the Herald on Sunday the government had all the required information to decide on the location for syndicate bases, but was unsure if a decision would be made about funding by Thursday when the council was due to make its final decision so a resource consent application could be submitted by mid-January.