The giant side profile is done by a really cool British artist who go's by Phlegm. It's also worth noticing the sick tag UFOOLER that is on the same wall by the figures eyeball. One of Aotearoa's best handstyles. The small scale heads that you like are done by DSIDE, a highly prolific street artist with works all over the country, both illegally and legally.
RE: Wellington, a town of street art - Part 1