One thing they should get is a really good writer to get a better story. The two last ones were decent, to put it nicely. Nothing compared to FOA (i know, i'm biased) with its enduring references to real history.
And if it absolutely has to be in 3D, get a real good engine. The DOOM3 Engine from id, or, if there's the need for huge landscapes, the UT2K4 Engine and modify it. And don´t even think about porting the game to a console.
It will only lower the overall quality because of the lowest common denominator.
Edit: Actually, i think the ET engine was quite good. But the artwork department was somehow limited (especially the polygone count)because of console hardware, which made the game look as if it was a few years old, at least partially.
[Edited by Adventurer on 10-06-2003 at 05:34 am]