After going through the requests in this post, I would say that most of them are implemented by now in a very satisfactory way through Mackx's hack of the rc3 update and his port of Xournal for instance. Of course for some (most?) users, that is probably a bit late. In addition, there is the for me crucial djvuplugin by luite and FBreader can read most of the other formats. Same thing on the DR800 with Iņigo's hacks and ports.
For me, the only remaining issue on the DR1000 is the somewhat slow boot time, as compared for instance to the DR800 and of course battery life. But charging it every couple of days is not such a big deal for me after all, especially considering that one really can read and work with those A4 pdf's. Reading epub's on the DR800 is a real pleasure and pdf's can be dealt with in a satisfactory way, but of course it is a bit more cumbersome than on the DR1000.
A minor request not really relevant for reading, and not directed to irex obviously but to those developers out there, would be to make usbnet ported by GregorRichards for the DR800S(G) work on the DR1000 as well.
On the DR800SG, it is of course a pity that the 3G cannot be used, especially since midori has been ported by now. So, the only request, which I also have seen formulated in some of the other threads, would be to be able to control and connect through a SIM card bought from a local provider. Imagine being able to check mail on the train on the DR800 ...
With usbnet and the terminal emulator ported, the often requested feature to be able to use the DR's as a wacom tablet for the PC also seems within reach.