I won't blindly say enabling 4GB + support in a 32 bit Windows is completely useless. As you said,there might be some benefits in case of running some huge apps simultaneously. But the real question is whether it worth the risk ?. As you already know, PAE patch will modify the Winload.exe ( a very critical OS system file) and also disables the integrity check. By doing this, you are opening all the doors and Windows of your system to an attacker or a Rootkit. Since there is no integrity check, a well programmed malware can easily hijack core Windows files including the Kernel. Also patching the files might affect the system stability ( OP is an example).
For whatever reasons, Microsoft decided not to enable 4GB + support in 32 bit consumer operating systems. When it came to Windows, i only trust Microsoft as they are the only one who know the source code. So if i want 4GB + support, i will choose a 64 bit OS rather than patching the core Windows files and compromising the stability and security of my system.
Edited by Anshad Edavana, 31 December 2013 - 02:33 AM.