As you stated before about the stock messaging app. You can delete this being that you have an aftermarket one BUT you will NOT be able to send and receive picture messages. It's best to just leave it.
I go through and uninstall ALOT of things in titanium. If your not sure jsut google it and see what it is.
Here is a list of "unusual" items not normally uninstalled that I have uninstalled.
Application manager
Android Live Wallpapers
AppwidgetPicker
BluetoothShare2.3.4
Clock2.0.2(I have aftermarket alarm)
Com.android.dun.server2.3.4
Contacts2.3.4(I have aftermarket contacts app)
Downloads
Drm Protected content storage
Drmservice
Email
Gmail
Googlesearch
Lg Hidden menu
Live wallpaperpicker
magic smoke wallpapers
maps
marketfeedbackagent
metropcshiddenmenu
metroweb(aftermarket browser)
music
musicwallpapers
musicwidget
myuploads
oma-dm
picotts
powercontrolwidget
searchappsprovider
streetview
allTTSand voice stuff
VPNservices
WAPservice
With this being said it's obvious what features I DONT use. Music,bluetooth and uploading things to my phone. If you use these don't uninstall them.
Every ROM I've ever installed I always uninstall these items and have never had a problem with my phone. It helps to keep down system process running in the background as well which eats up battery.
Make a backup and if you are ever unsure about uninstalling an app, google it.
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