If you want to start other programs than PStart.exe then you need to modify file
startnet.cmd located in PE3_mod\PE3_add\x86\Windows\System32 folder
In this way you can easily control what is running at Startup.
Other keyboard layout will be possible, but I have no experience with that yet.
In general I resize application windows such that PStart Window remains visible at the right edge of the screen.
PStart windows serves then as taskbar. May be we can add to the build a shell with real taskbar as you described.
PStart will keep a record of windows size and position, such that on next boot you get your last size.
The present approach keeps the boot image small, which is good for fast booting (30 sec from HDD or 4 min from USB-stick).
Building the pe3.iso boot image with Make_PE3.cmd is very fast, about 2 minutes.
Also you have easy control of what is added to the build and you don't need a Windows 7 Setup DVD.
You simply make use of files and registry settings of installed Windows 7 operating system to improve Windows PE 3.0
Once these files and settings are collected in
WIN7_add and
PE3_reg folder, you don't need even any more the Installed Windows 7 as source.
To add a WLAN device driver to a Running Windows PE 3.0 you type at the command prompt:
drvload.exe <inf_path>
You can specify multiple inf files by separating each inf file entry with a comma.
Make_PE3.cmd uses the Deployment Image Servicing and Management (DISM) tool to add drivers to the Windows PE 3.0 ISO Boot Image.
Add your Driver files e.g. for WLAN in folder
PE3_mod\WIN7_drivers\x86 (recurse scanning allows subfolders with driver files)
The Portable Programs running from PStart Menu are not part of the ISO Boot Image,
so that you can easily make program changes without the need to rebuild the ISO file.
Moreover, you can use the Portable Programs on any occasion, e.g. also without booting from the Windows PE 3.0 ISO
Building Win7RescuePE/Win7PE with Winbuilder involves adding programs to the build and you need a Windows 7 Setup DVD as Source.
Program changes require to rebuild in about 12 minutes with WinBuilder to make a new ISO.
This is less flexible and makes the build much larger and the programs cannot be used easily without booting.
Win7PE is similar in booting and one can use grub4dos ISO emulation to boot from HDD or from USB-stick,
but Win7Rescue PE (500-600 MB). In both cases I was not able to connect Wireless with Internet.