Yes, you can. About the ground FOW you talk about, it's one of most irritating things (fixed in EaW:TR
). To extend ONLY the FOW in land and/or space (not attack ranges etc etc), you must edit the entry:
They can be found in the unit description you're looking for. For example, to edit T4B fow range, you open Groundvehicles.xml, to edit Corellian Corvette's fow range, you open Spaceunitscorvettes.xml and so on.