There's a pattern that emerged from the Wellington in 2040 analysis which I should have already realised, but that I've never consciously thought of: a particular similarity between Melbourne's Hoddle Grid and the Te Aro street pattern.
One thing that I like about Melbourne's CBD is the alternation of wide streets (such as Flinders St, Collins St and Bourke St) with much narrower ones (Flinders Lane, Little Collins St and Little Bourke St). The wide streets, while being primarily about movement, still have plenty of retail activity, though it tends to be mainstream or upmarket and in some blocks gives way to grand civic or commercial buildings. The "little" streets have a much greater variety of retail and hospitality, and their intimacy and activity makes up for any griminess and lack of sun.
Rotate this pattern by about 45 degrees anticlockwise, and it looks like we've got the beginnings of a similar alternation in Te Aro. Victoria St, Taranaki St and Cambridge/Kent Tce are the relatively wide and fast streets; Willis, Cuba and Tory streets are slower, narrower and along much of their lengths, blessed with more active edges and independent retail.
How could we build on this pattern? Apart from the ideas presented last week, my own suggestions would be to make the fast streets more like boulevards (with more trees, and by filling in the vacant and low-rise gaps in the urban fabric) while stepping up pedestrian priority in the slow ones. While there have been some encouraging recent changes, I don't ever expect Taranaki St to become a café and retail destination: a better strategy would be to aim for a dignified thoroughfare with the gradual accumulation of active edges. The slow streets could also handle some slightly higher-rise development, since the slow streets of Melbourne seem to maintain intimacy and vitality despite (or perhaps due to?) often being lined by tall buildings; and the emphasis should be on removing through traffic where possible and making active edges mandatory.
That may not work for the whole length of those streets (upper Willis is likely to remain quasi-suburban in character, for example, and Victoria Street's ad-hoc twists and left-over corners will present a challenge), but it could be the start of a general pattern to aim for. It could improve legibility and memorability, since it'll be harder to think of any of these as "just another street": they will have a place in a hierarchy. It will help distribute different urban conditions (the grand and the intimate), and provide a simple framework to guide development. Combine that with trams, mature street trees and populated laneways, and Te Aro could look and feel a lot better in a few decades' time.
I'm not saying that we should ape everything that Melbourne does, and it won't have that effect since Wellington's harbour, hills and climate will always create a unique setting. But Melbourne has created a famously liveable and lively city on its particular version of the well-known gridiron, and the alternation of fast & wide with slow & narrow may have something to do with that.