[T-Mobile, Samsung Galaxy SIII] TheLastSidekick:
I know there was a post just like with what I'm doing...but here's something for you to use in your own ROMs.

#Performance Enhancement
dalvik.vm.heapgrowthlimit=256m
debug.performance.tuning=1
windowsmgr.max_events_per_sec=300
ro.max.fling_velocity=12000
ro.min.fling_velocity=8000
debug.sf.hw=1
video.accelerate.hw=1
profiler.force_disable_err_rpt=1
dalvik.vm.dexopt-flags=m=y
dalvik.vm.execution-mode=init:jit
ro.kernel.android.checkjni=0

#Battery Enhancement
ro.ril.disable.power.collapse=0
pm.sleep_mode=1
wifi.supplicant_scan_interval=500
ro.mot.eri.losalert.delay=1000
persist.sys.purgeable_assets=1

# Signal Enhancement
ro.ril.enable.dtm=1
ro.ril.hsdpa.category=28
ro.ril.enable.a53=1
ro.ril.enable.3g.prefix=1
ro.ril.htcmaskw1.bitmask=4294967295
ro.ril.htcmaskw1=14449
ro.ril.hsupa.category=7
media.stagefright.enable-meta=true
media.stagefright.enable-record=false
ro.ril.hep=1
net.ppp0.dns1=8.8.8.8
net.ppp0.dns2=8.8.4.4
net.dns1=8.8.8.8
net.dns2=8.8.4.4
net.tcp.buffersize.default=6144,87380,1048576,6144,87380,524288
net.tcp.buffersize.wifi=524288,1048576,2097152,524288,1048576,2097152
net.tcp.buffersize.umts=6144,87380,1048576,6144,87380,524288
net.tcp.buffersize.gprs=6144,87380,1048576,6144,87380,524288
net.tcp.buffersize.edge=6144,87380,524288,6144,16384,262144
net.tcp.buffersize.hspa=6144,87380,524288,6144,16384,262144
net.tcp.buffersize.lte=524288,1048576,2097152,524288,1048576,2097152
net.tcp.buffersize.hsdpa=6144,87380,1048576,6144,87380,1048576
net.tcp.buffersize.evdo_b=6144,87380,1048576,6144,87380,1048576

# Video & Picture Enhancement
ro.media.enc.jpeg.quality=100
ro.media.dec.jpeg.memcap=8000000
ro.media.enc.hprof.vid.bps=8000000

# Sound & Calls Enhancement
ro.telephony.call_ring.delay=0
ro.semc.sound_effects_enabled=true
ro.semc.xloud.supported=true
persist.service.xloud.enable=1
ro.semc.enhance.supported=true
persist.service.enhance.enable=1
ro.semc.clearaudio.supported=true
persist.service.clearaudio.enable=1
ro.sony.walkman.logger=1
ro.somc.clearphase.supported=true
persist.service.clearphase.enable=1
af.resampler.quality=255
persist.af.resampler.quality=255
htc.audio.swalt.enable=1
htc.audio.swalt.mingain=14512

#AC!D Audio Volume Hack
-----------------------------
speaker volume is from 20 to 31
this corresponds to -2dB to +8dB
-----------------------------
audio.speaker.voice.0=20
audio.speaker.voice.1=21
audio.speaker.voice.2=24
audio.speaker.voice.3=26
audio.speaker.voice.4=28
audio.speaker.voice.5=31
-----------------------------
earpiece volume is from 20 to 31
this corresponds to -2dB to +8dB
-----------------------------
audio.earpiece.voice.0=20
audio.earpiece.voice.1=21
audio.earpiece.voice.2=24
audio.earpiece.voice.3=26
audio.earpiece.voice.4=28
audio.earpiece.voice.5=31
-----------------------------------
headset volume is from 9 to 14
this corresponds to -34dB to -19dB
----------------------------------
audio.headset.voice.0=16
audio.headset.voice.1=19
audio.headset.voice.2=22
audio.headset.voice.3=25
audio.headset.voice.4=28
audio.headset.voice.5=31

#Sony BRAVIA Engine
ro.service.swiqi.supported=true
persist.service.swiqi.enable=1

Note ** : Bravia Engine build.prop and AC!D build.prop edits still need required files. This is just to enable the settings to work with the files.