The most important thing. Back up your user data!! You cant harm your device since you can almost in any case master reset but when performing master reset the internal storage will be erased. Back up your registry as well. Some services, networks and relateed stuff may stop working.
Every time WM boots, system writes amount of free memory. Check it and compare free memory spare after performing selected tweaks.
HKCU\Performance\Available RAM on boot
I have performed master reset, set Default homescreen (WeatherUpdateService take too much ram space), installed Resco Explorer, Registry Editor, Celetask, and Oxios Memory. Micro SD is inserted but all programs are stored in internal memory.
Do not continue without registry backup (PHM Registry Editor works fine) and back up of user data from internal memory (Sprite Backup)!
Tweaks:
Safe to modify.
At your own risk.
Go to Start Menu -> Connection Setup and check if "Enable Auto Configuration" is turned off.
\Windows\StartUp (Delete)
btdwake.lnk
PKG.lnk
btdwake = Bluetooth Disk Driver (BT FTP)
HKLM\init (Delete)
Launch98: TimeWizard.exe
Launch99: SAPSettings.exe
Launch100: uptimesqm.exe
Depend100
Launch101: ConnectionSetupAuto.exe
HKLM\Services (Delete. Be vary carful with these keys! WM may not start if you delete needed key. Backup this registry if you would need these services in the future.)
App
BTAGSVC
BthAsPlugin
BTHIDSVC
CERTENROL
Clock
GPSDaemonService
HTCServices
OBEX
SDS
SNApi
SqmUpload
STK_service
USSD
Windows Live
HKLM\Services (Delete)
Trusted (this key cannot be deleted, so delete all values except "SIMInit: siminit.dll")