OK, going to try and clear up a few points at once here.
The E200MMC at 11.9m has the same size wheels as the E300 it replaces - smaller wheels (same as the old E200) are available on shorter lengths. Obviously the E300 always was a lightweight single deck, but I wouldn't say that the long E200MMCs are just oversized MDs. There's a big difference between bolting another 20cm onto a standard Dart to make an SPD, and having a range that goes all the way up to 12m.
E200MMC at 11.9m and the Streetlite MAX only share a platform with their shorter siblings.
480 units is about the right number, for comparison:
2009 - 434
2010 - 340
2011 - 580 (but includes a major investment of 163 units in the re-aquired London ops)
2012 -390
2013 - 430
2014 - 570 (a record £100m investment, presumably mostly due to the Astromegas for Oxford Tube)
2015 - 470
So as can be seen, this year's initial order is fairly typical, but unlike other years I would suggest there is limited scope for a further "extension" order in summer.
Further, based on the numbers I've seen, potention regulation in Manchester is not being seen as a hindrance to investment - at least not this year...
Gillmoss are due two batches of E400MMCs. In fact, the only depot not getting anything new in MY&SL will be Preston.