After much experimenting I think I found a way to display the splash menu without having to press a key first, and then displaying with the SHIFT or ESC key (any other key displays the countdown time remaining).

Dareus, if you are still interested let me know and I'll purge/reinstall GRUB so I know I'm working with the default scripts and not my variations. I'll try to figure out a script modification rather than a straight hack of the grub.cfg file so it can be done automatically.

It's been a giant puzzle but I won't pursue it unless someone wants to use this functionality.