The monspeed / animation fixes are not enough for me and CE Speedhack doesn't with this game (aside sprites). The solution I found is to use DxWnd's timestretching feature.

Firstly, 3dsetup.exe in game's folder must be configured to use DirectX7, or DxWnd won't affect the game (with default settings, at least).

Secondly, run DxWnd (I've used 2.05.48 version) and enable expert mode (Options menu > Expert Mode). This makes Timing tab visible in game profiles.

Then, Wizardry game profile must be created in DxWnd using Edit > Add.
1. At "Main" tab, define profile name "Wizardry" and path to the Wiz8.exe. Select "Desktop" at the bottom for borderless fullscreen. As a bonus, game now won't crash (so often) when alt-tabbing.
2. At "Mouse" tab uncheck "Correct mouse position" flag, or mouse buttons won't work.
3. At "Timing" tab, navigate to "Time stretching" group and check "Time Stretch - initial" flag, and select x2 for x2 speedup in the list to the right.
4. Click "OK".
* 5. Supposedly, speedup hotkeys can be configured in Options > Global Settings, Hotkeys (Alt + Hotkey). Didn't work for me, though.

If somebody really does not care about the animations, here is the way to speed things up:

Run madgods Cosmic Forge Editor, go to "miscellaneous", and select to "rummage W8 file collection",
open Wiz8Installdir\data\data.slf and extract the contents of the virtual folder \monsters.
In all .mls files, outcomment all sound related entries like "sound_frame*", "sound_footstep*" etc with a [#], aka hash/number sign
at the very beginning of the line, preferably with an automated process ;)
Additionally inrease the value for [movementrate] by at least 4 times, or whatever the game still accepts,
the old engine will probably have limits.

Now run CF -> tools -> 3D manager,
open every .mon animation file, delete all frames except one,
and set the fps value of the anim file to a value the game can still handle, 60 should be ok for all vanilla monsters.
This appears more effective than to use the mls script to increase anim speed

Now the sounds for different actions must be replaced with a very short audio file,
in detail from the sounds.slf archive extract all files in vitual folder \combat,
and all files in file data\sound\monsters\monstersound .slf.

This will compare to any existing speedmod like a cheetah to a sleuth.

To complete the job, all [velocity] values in mls files for missiles and spells should be increased to at least 250.

And if that is not enough, use e.g. cheat engine to run the whole game at e.g. 4x speed.

You also can just disable sound entirely in 3dsetup (select "None" driver). I've set "Dolby Surround' driver. Like this, sound is lost only partially, but things still run fast like without sound. Sadly, no voice.
I wonder if the game can be patched to play battle sounds asynchronously...