In Praise Of... The Victoria Line
A decade ago, when the Jubilee Line was extended from Green Park to Stratford, there were plenty of glossy books published, examining the design and architecture of the twelve stations that made up the extension. Deservedly so, too; one, Foster's Canary Wharf, has become iconic in that time. There's still plenty you can find about the philosophy of the designers, and the way they wanted a commonality but individuality for each of the stations.
By contrast, it's almost impossible to find out about the thinking behind the Victoria Line. This was only all-new Underground line in the last century¹, and it's forty years old this year. Most people, if they think of its design at all, consider it dull at best.
However, I've been using it for my commute for a year now, and as a primary line for half a decade, and I think that does it a disservice. First, consider the station layouts. This is, I'll admit, more commonly thought of as engineering, but even so, someone had to think about it. There are sixteen stations on the line; five have cross-platform interchanges with either Tube or British Rail lines, far more than any other line², while all but one station offer interchanges with either Underground or British Rail lines.
Admittedly, partly this is due to politics: during the "tube boom" from 1898 to 1908, the organisations building lines were in competition with one another, whereas the Victoria was the first line designed by London Underground, a single company responsible for all lines. Even so, it's a boon to people who use the line - ask anyone who changes to the Piccadilly at Finsbury Park, or the Bakerloo at Oxford Street.
Beyond the engineering, though, I think the stations are also designed well. Unlike the aforementioned Jubilee Line, most stations follow the same basic look, with three escalators³ down to a main hallway between the two platforms. Unlike some earlier lines (the Central Line springs to mind), these are almost always straight, and I can't think of a station with steps from the central section to either platform. As I've said before, there are also cross-platform interchanges, which complicate things, but even there, consistency leaps out in other ways.
All of the Victoria Line platforms are tiled in a light, almost blue-tinted, grey, with simple wooden benches. Each also has a mural; there's a lovely set on Flickr by Chutney Bannister collecting them all. Recently, the southbound Oxford Street tiling was refurbished as part of the station's PPP makeover, and I was impressed by the lovely, modern design that replaced the snakes-and-ladders mural you can still see on the northbound platform. It turns out that this was the original design, removed in the 1980s after the Oxford Circus fire, but now re-instated, and it doesn't look at all dated - in fact, it's positively modern.
For now, the original 1967 tube stock is still used on the line. However, next year should see the introduction of the new 2009 stock, which, to be honest, I'm somewhat dreading. As with the stations, these are nicely consistent and minimal, with a quirky use of circular glass panels dividing vestibules from seating areas, and standard seating. The new stock will introduce more fold-up seats, and more room to stand, at the cost of fixed seats. I suppose I should wait and see how it turns out, but my gut feeling is that I'll dislike them.
That's not to say the line is without problems. As part of the engineering work to get the line ready for the new trains, its previously solid reliability seems to have taken a knock. More seriously, the above-ground buildings are generally appalling, with far too many of the stations lumbered with unpleasant subway complexes or buildings that look like glorified portakabins. This is particularly shameful at Highbury and Islington, where a damaged but glorious old station was demolished in favour of the current single-storey shed.
Despite this, I think the effort going into the line has been unfairly neglected. The design work for the Victoria line seems to be largely lost, on the Internet at least. Mischa Black was in charge of the overall design effort, leading the Design Research Unit, but I can easily imagine how the utilitarian style leant itself to concealing the identities of the others who contributed. I think it's a shame; the line, while perhaps understated, deserves more attention than it gets. I can't imagine my London without it.
¹ Parts of the Jubilee line were inherited from the Metropolitan line in 1977, and of course the extension in 1999, while needing new tracks, was not a new line end-to-end. Amazingly, the Central London tube network we know today - with the exception of the Victoria and Jubilee lines - was completed by 1907.
² I believe the Central, District and Piccadilly each have two, excluding Victoria Line interchanges, but none are within zone 1 (I'm thinking of Stratford, Mile End, and Hammersmith).
³ Annoyingly, cost-cutting sometimes (as at my home station, Blackhorse Road) led to the central escalator being replaced by a fixed staircase, which means that any failure results in people having to walk or, in extreme cases, station closures.

Comments
Barons court(certainly westbound) and acton town(again certainly westbound). Turnham green as well but since the piccadilly only stops there early morning and late at night it probably doesnt count.
That's not to say that the ones you list aren't useful, but the engineering involved isn't as impressive as that on the Victoria Line.