Okay, I've won with the SPB Mobile Shell installation - and learnt a lot about WinMo in the process!
I really have to recommend the SPB Shell to anybody who owns a WinMo device - including the Omnia. Even without all the extra themes, SPB Shell is a great addon for your device.
I have now set up my Omnia as follows:
TODAY SCREEN = SAMSUNG TODAY1 (and nothing else)
LEFT SOFTKEY = NOW SCREEN (Part of SPB, which shows your diary, time, notifications, etc.)
RIGHT SOFTKEY = DIALLING TAB (Part of SPB, which allows a dozen or so dialling shortcuts)
MAIN MENU KEY = SPB MENU
As a result, I now literally have everything I need at my fingertips. I really don't need a stylus anymore at all, since SPB is much more finger-friendly. Yes, it costs $30US, but I reckon it is worth every penny!
BTW, how can I take screen-shots of my device? Would like to post them here so you can see how cool SPB is.