El reg could have done a better job at reviewing this
Battery cover on E series is part of the antenna. Good luck getting WiFi or Bluetooth to work without the cover. No panache there, it is functional.
Similarly, the CPU is there not just for multitasking. The E72 and especially the E71 gives up the ghost trying to do VOIP on WPA2 wifi. You have to stick with WEP even for g711 codecs. They do not have enough grunt for todays smartphone world so pushing the CPU a bit is badly needed.
Navigation screen size is actually not that bad. Just put it in the right place - by the rare view mirror. It is perfectly reasonable (I have driven 4000miles+ across all of EU with E71 which has the same screen size). If you put it somewhere far in front where most people put their GPS you will indeed find it too small.