Well the Greens are unhappy (but building a road and not building a steel church - I mean light railway - means that is guaranteed), but the plan itself as reported in Stuff isn't half bad. A new flyover at the Basin Reserve (long been planned and necessary) will make a big difference as will widening Wellington Rd and Ruahine St. Bus lanes through town and down Cambridge and Kent Terrace could do some good (especially if taxis and trucks are allowed on them too), so all in all a reasonable way to spend some fuel tax.
The ridiculous light rail fetish, which few of the enthusiasts accurately cost on a per passenger km basis, should be killed. However, second Terrace Tunnel and Mt Victoria Tunnel would be good - but there is no talk of tolls which could fund them. I'd argue that State Highway 1 could be privatised and that would incentivise construction of a decent bypass as it could have variable tolls by time of day, but there is little appetite for this in Wellington.
Oh and while the Wellington Mayor is enthused, note no MPs will get fired up about modest good road projects - they don't see votes in them (unlike Peter Dunne's fetish with Transmission Gully), so they often get neglected. Not even the Transport Minister, Annette King, whose electorate would benefit enormously from improving the roads between the city and the airport, is too interested - but then maybe she's looking at what her job is after the election?