[Touch Diamond, MDA Compact IV General] legend221:
There are so many pages to go through so please excuse if a registry tweak is repeated below:

Homescreen Optimization (Chome)​

Description: Disable SMSMMSOverride

HKLM\Software\Microsoft\CHome\SMSMMSOverride=0

No Beep​

Description: No Beep

HKCU\ControlPanel\SoundCategories\Cal lStart\InitVol=0

SMSDeliveryNotify​

Description: SMSDeliveryNotify

HKLM\SOFTWARE\Microsoft\Inbox\Settings\SMSDeliveryNotify=1

TF3D 2 Start Menu​

Description: Disable Manilla

HKCU\\Software\HTC\TaskManager\ExclusiveList\System\manil2.exe=0

Contacts​

Description: Hide Sim Contacts

HKCU\ControlPanel\Phone\ShowSIM=0

Internet Increase Max Connect​

Description: Max Connection Per 10

HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\MaxConnectionsPer1_0Server=20

Description: Speed Up Internet Access

HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings\MaxConnectionsPerServer=10

Manila​

Description: Facebook in Manila

HKLM\Software\HTC\Manila2D\InternetWidget\Customized\CustomizedCount=2

Description: Manila Home

HKCU\Software\HTC\Manila\HomeBackgroundPath=\Windows\Sfondo.jpg

Custom Video Recording Resolution​

Description: Add 400x240 widescreen video recording

HKCU\Software\Samsung\Camera\VideoSize=1653

Rom Install​

Description: FATFS Cache Size

HKLM\System\StorageManager\FATFS\CacheSize=32768

Description: Improve Scrolling

HKLM\Drivers\TouchPanel\PressureThreshold=00013be2

Sounds​

Description: Active Sliding Sound

HKLM\Software\HTC\SlidingSound\ActiveSlidingSound=dword:00000000

Description: Sliding Sound

HKLM\Software\HTC\SlidingSound\SlidingSoundEffect=dword:00000001

HTC Album​

Description: Change HTC default for bitmap

HKCR\bmpimage\Shell\Open\Command\defaultbitmap=HTCAlbum.exe /%1

Description: Change HTC default for gif

HKCR\ jpegimage \Shell\Open\Command\defaultgif=HTCAlbum.exe /%1

Description: Change HTC default for jpeg

HKCR\ jpegimage \Shell\Open\Command\defaultjpeg=HTCAlbum.exe /%1

HTC Diamond Audio Increase​

Description: Boosts Audio Embedded

HKLM\SOFTWARE\HTC\AUDIOGAIN\EAC_GAIN_EMBEDDED=300

Description: Boosts Audio Headset

HKLM\SOFTWARE\HTC\AUDIOGAIN\EAC_GAIN_HEADSET=77

Description: Increase Max Ringtone Size

HKCU\ControlPanel\Sounds\FileSizeLimit=9999999

Change Java Fonts​

Description: Increases the Medium font size In Java

HKLM\SOFTWARE\Apps\Esmertec Java\Device Info\Java Font\Size Medium=200

Description: Increases the Small font size In Java

HKLM\SOFTWARE\Apps\Esmertec Java\Device Info\Java Font\Size Extra Large=200

Description: Increases the Small font size In Java

HKLM\SOFTWARE\Apps\Esmertec Java\Device Info\Java Font\Size Large=200

Pocket IE Tweaks​

Description: Pocket Internet Explorer Left D-Pad button page up.

HKLM\Software\Microsoft\Internet Explorer\KeyMaps\37=1

Description: Pocket Internet Explorer Right D-Pad Button page down.

HKLM\Software\Microsoft\Internet Explorer\KeyMaps\39=2

Description: Velocityexp.com

HKCU\Software\Microsoft\Internet Explorer\Main\Velocityhomepage=http://Velocityexp.com

Screen Sensitivity​

Description: Screen Sensitivity

HKLM\HKEY_LOCAL_MACHINE\Drivers\TouchPanel\PressureThreshold=PressureThreshold

Description: Screen Sensitivity

HKLM\Drivers\TouchPanel\PressureThreshold=200\PressureThreshold=PressureThreshold

Description: Screen Sensitivity

HKLM\Drivers\TouchPanel\PressureThreshold=200\PressureThreshold=200

Description: Adjust Touchscreen Reception To Max

HKLM\Drivers\TouchPanel\PressureThreshold=FFFFFFFF

Sound Notification​

Description: Charger Disconnect Sound

HKCU\ControlPanel\Volume\ChargerDisconnectSound\File=Chargeroff.wav

Description: Disable Charger Connect Sound

HKCU\ControlPanel\Volume\ChargerConnectSound\File=ChargerConnect.old

Description: Disable System Start Sound

HKCU\ControlPanel\Sounds\SystemStart\Sound=\Windows\ind.wav

Description: Enable Low Battery Warning Options to Notifications

HKCU\ControlPanel\Notifications\{A877D663-239C-47a7-9304-0D347F580408}\Default=Low battery warning

Input Method​

Description: Make FingerKeyBoard 2 Default Sip

HKCU\ControlPanel\SIP\DefaultIM={C03755DF-3EE7-41DF-AE5E-3FBBCA603F1A}

Phone LED​

Description: Email LED

HKCU\ControlPanel\Notifications\{A877D65A-239C-47a7-9304-0D347F580408}\Duration=0

Description: Missed Call LED

HKCU\ControlPanel\Notifications\{A877D660-239C-47a7-9304-0D347F580408}\AvailableOptions=0

Description: New MMS LED

HKCU\ControlPanel\Notifications\{C3465585-39EF-4c9b-B2A3-5558BF27BFB0}\AvailableOptions=0

Description: Text message LED

HKCU\ControlPanel\Notifications\{A877D65B-239C-47a7-9304-0D347F580408}\AvailableOptions=0

Description: Voicemail LED

HKCU\ControlPanel\Notifications\{A877D661-239C-47a7-9304-0D347F580408}\AvailableOptions=0

SMS Tweaks​

Description: Disable Account Picker

HKCU\Software\Microsoft\Inbox\Settings\AcctPicker=0

Description: Disable Sent SMS MSG

HKLM\SOFTWARE\Microsoft\Inbox\Settings\SMSNoSentMsg=1

Description: Disable SMS Theading

HKCU\Software\Microsoft\Inbox\Settings\OEM\SMSInboxThreadingDisabled=1

Description: Enable SMS Wake Up

HKLM\drivers\builtin\ril\DisableSMSWakeUpEvent=0

Description: Enable Threaded SMS Messages

HKLM\Software\Microsoft\Inbox\Settings\OEM\SMSInboxThreadingDisabled=0

Word Completion​

Description: Enable WordCompletion

HKCU\keyboard layout\preload\default=e0010409

Description: Old Word Completion part 1

HKLM\Software\Tegic\eT9\XT9SupportMSSip=0

Description: Old Word Completion part 2

HKLM\system\currentcontrolset\control\layouts\e 0010409\Ime File=\windows\compime.dll

Description: Old Word Completion part 3

HKLM\system\currentcontrolset\control\layouts\e 0010409\Layout Text=COMP IME

Accelerometer Tweaks​

Description: Enable Manual Rotation with Long Key Press

HKLM\System\GDI\Rotation\HideOrientationUI=0

Description: Enable Manual Screen Rotation

HKLM\System\GDI\Rotation\HideOrientationUI=1

Description: Keep Screen On When Answering Calls

HKLM\Drivers\BuiltIn\RIL\EnableFastDormantDisplayDuringCall=0

Description: Keep Screen On When Answering Calls for EU ROMS

HKCU\ControlPanel\Phone\Sleep=1

Description: Mute Call by Flipping Phone Face Down

HKLM\Software\HTC\PHONE\FaceDownMuteRing=0

Description: Speed Up Screen orientation speed

HKCU\controlpanel\accelsensor\adjust delay=0

Audio and Video Tweaks​

Description: 50-InCall Volume Boost

HKCU\Control Panel\SoundCategories\InCall\InitVol=95

Description: Enable Audio Booster Without Headset

HKLM\System\State\Hardware\Headset=1

Description: Improve SNR for FM Radio

HKLM\Software\HTC\FMRadio\FMPlayer\Deemphasis=1

Description: Ring on call at normal volume

HKCU\CONTROLPANEL\SOUNDCATAGORIES\INCALL\INITVOL=4

Description: RingToneDelay

HKCU\ControlPanel\Sounds\RingTone0\Script=apr

Description: Vibration and Incremental Ring

HKCU\ControlPanel\Sounds\RingTone0\Script=apr

Description: Windows Media Player play w/o Backlight

HKLM\Software\Microsoft\MediaPlayer\Preferences\UnattendedPlayback=1

HTC Diamond Specific​

Description: Disable Shutdown Animation

HKLM\Software\HTC\PowerOff\PlayShutdownAnimation=0

Description: Disable Shutdown Animation Image

HKLM\Software\HTC\HTCAnimation\ShutDownGif=\windows\na.gif

Description: Disable Shutdown Animation Sound

HKLM\Software\HTC\HTCAnimation\ShutDownWav=\windows\na.wav

Description: Enable removing programs after installing Manila2

HKLM\Security\Policies\Policies\00001005=24

Description: Regedit 4 IMplus

HKLM\Comm\TcpIp\Hosts\shapeservices.com\ipaddr=hex:7F,00,00,01

Description: Screen Rotation

HKLM\System\GDI\Rotation\HideOrientationUI=0

Description: Startup No Animation

HKLM\Software\HTC\HTCAnimation\StartupGif=\windows\na.gif

Description: Startup No Sound

HKLM\Software\HTC\HTCAnimation\StartupWav=\windows\na.wav

AND MORE TO COME VERY SOON! Please remember that these are registry changes that may or may not make your system unstable so you perform these AT YOUR OWN RISK. Once I get my Diamond sometime this week I will test these personally. I am hopeful everyone comes out good results...