i thought it would be cool to fly through cities and such. it would make for a nice tense field of battle, have to dodge a whole sort of things trying to kill you, whle weaving and blazing throught cities. imagine Thor flying down your street. thats what i want.
ok - Because you are already in the city, the Freespace lodding system won't work.
A simple city is easy to make. The more complex you make it, the more you have to juggle within the limitations.
Keep the landscape as low poly as possible. Height maps are the most common way to generate the landscape polys. Use one large texture map or go for tiling. (For tiling - google high pass filter) The landscape will always be a balance between what looks good close vs far. Make a flat piece for the buildings to sit on. Having this separate from the landscape means you can texture it a different way. (roads etc)
If you can keep most of the buildings to simple extruded shapes, then you can skip detail boxes.
Make 8-16 buildings, depending on how interesting you want the city to look - (recommend 8 for version 1)
UV map at least 4 buildings per map. You will be mostly zooming past them so you don't need to get too fancy.
Don't add extra poly details to buildings - use texture maps. Plan to use normal maps to simulate polys.
Once you place the buildings
Select all the buildings using the same texture map and merge them into one poly object.
If the poly count for any object is more than 9k (approx) then you will need PCS2 for pofing. If you hit this limit you either missed the keep it simple part or like lots of buildings.
A good sky box makes a difference
Since this method is not using detail boxes - don't go crazy on poly count.
In a nutshell ----> Less objects and Less texture maps = better