Not the smartest dude, but i love android emulation and know my sh*t 
GFX:
Backend: OpenGL (dunno how's it gonna be with android Vulkan)
Mode: Buffered rendering (non-buffered, gives somewhat better fps but its a mess imo)
Simulate block transfer effect: On (default)
Frameskipping
I highly recommend using Auto-Frameskip and Prevent FPS from exceeding 60.
Postprocessing shaders: Personal Preference (some shaders impact performance)
Rendering resolution: 2xPSP (looks great on 720p screens)
Mipmapping,Hardware transform,Software skinning, Vertex cache, Lazy texture caching and disable slower effects should be enabled.
Texture scalling
I keep all that jazz off
Texture filtering
Anisotropic filtering: Off (16x by default for some reason :? )
Texture Filtering: Auto
Hacks
As far as hacks go i enable Timer hack and Texture coord speedhack
Audio
Enabled with latency on high without resampling or the DOA sound hack
System
DO NOT ENABLE MULTITHREADED, seriously don't can overheat ur phone pretty easly.
Anything that i left out probably means that its personal preference or doesn't affect performance.
I am using custom roms which improve performance, but most settings should work just fine on stock as well.
GFX:
Backend: OpenGL (dunno how's it gonna be with android Vulkan)
Mode: Buffered rendering (non-buffered, gives somewhat better fps but its a mess imo)
Simulate block transfer effect: On (default)
Frameskipping
I highly recommend using Auto-Frameskip and Prevent FPS from exceeding 60.
Postprocessing shaders: Personal Preference (some shaders impact performance)
Rendering resolution: 2xPSP (looks great on 720p screens)
Mipmapping,Hardware transform,Software skinning, Vertex cache, Lazy texture caching and disable slower effects should be enabled.
Texture scalling
I keep all that jazz off
Texture filtering
Anisotropic filtering: Off (16x by default for some reason :? )
Texture Filtering: Auto
Hacks
As far as hacks go i enable Timer hack and Texture coord speedhack
Audio
Enabled with latency on high without resampling or the DOA sound hack
System
DO NOT ENABLE MULTITHREADED, seriously don't can overheat ur phone pretty easly.
Anything that i left out probably means that its personal preference or doesn't affect performance.
I am using custom roms which improve performance, but most settings should work just fine on stock as well.