I may be able to help you with this if I understand the problem.
here's what I have recently done.
PXE system used for server installations was recently updated to add boot image from network option.
(I use debian, so you may need to tweak some of the steps)
I created my gold image by performing a standard installation to the local hard disk of one system.
I then updated the initramfs to boot from nfs, and then copied the entire image into the pxe boot directory.
-- Use the kernal & initrd from the gold image as your new kernel & initrd in the pxe system.
Update your pxe server to do the following:
Set the default boot item to be the system image you want, and then set the boot timeout to 5-10 seconds.
This gives you time to select an alternate boot image if required, but by default the system will always
boot to the system image.
So my configuration now looks something like this:
default = full system image. boots from network image, and is about 4x faster than local disk boot.
timeout ~ 5 seconds.
Works nicely. systems just boot to the system image by default, but I still have the option to perform a full install
at any time via PXE.