I finally got around to listening to Prospekt's March...
Great
Rainy Day
Pretty good
Glass Of Water
Prospekt's March/Poppyfields
Now My Feet Won't Touch The Ground
Inessential
Life In Technicolor II
Postcards From Far Away
Lost+ (feat. 5 seconds of Jay-Z)
Lovers In Japan (Osaka Sun Mix)
Overall, there was nothing I really disliked, and nothing I would really place on the album proper, excepting perhaps Rainy Day, which is fantastic. LIT2 is utterly pointless, and CMart's vocals are awful, while Postcards From Far Away could make for a nice intro. The remixes are remixes, eh. Prospekt's March/Poppyfields is cliche, mid-range Coldplay that sounds nice enough, Glass Of Water is pleasant, but not exactly album-worthy, and the same could be said of Now My Feet Won't Touch The Ground, which never really builds to anything.
If Viva La Vida is a B+, the EP gets a B-. This era of Coldplay is miles ahead of 2005-2007, and the EP caps it off nicely. But this isn't anything I would recommend to newcomers.