optimise your shadow sizes. Use light linking to only illuminate objects that need to be illuminated by that light, dont use GI_Joe, if you are raytracing then only raytrace objects that need it, use render layers to reduce re-rendering , use 2d images on planes where possible, use LOD (not maya's though cause it sucks ass)
that's about it really as far as I can think of.
Technical Director - Framestore
Currently working on: Your Highness