These are the settings I use for maximum performance and stunning visuals. With the exception of very high density areas (Seattle), I am able to maintain >60fps in every location I fly.
P3D v4 Application Settings. *Pause On Task Switch turned off because I use multiple monitors*
P3D v4 Information Settings. *I keep vehicle labels turned off to train my eyes to spot aircraft*
P3D v4 Sound Settings. *Voice turned off because I use external ATC program called Oncourse PF3*
P3D v4 Traffic Settings. *Airport Vehicles turned off because I use GSX Level 2*
P3D v4 Realism Settings. *These settings allow water assisted landings in bush planes*
P3D v4 Display Settings. *VSync On removes stutters*
P3D v4 World Settings. *Crisp and fast texture loading*
P3D v4 Lighting Settings. *Crisp and fast shadow textures and behavior*
P3D v4 Weather Settings. *I used REX clouds with 2048 resolution*