Wow, thank you for your confidence. One of the quiet movements of the past several years is the slow migration of Palm software developers to the PPC/WM platform. A number of popular programs are available on both sets of devices now.
That said, datebk isn't one of those. The loss of datebk was my #1 concern upon switching platforms. Pocket Informant was recommended to me at the time and I've been using it since the beginning. The developer is responsive to user issues, and keeps his software at the top of the PIM heap IMO. It's very easy to use, but like datebk, takes a while to work through all the configuration options. PI looks great on the VGA screen and plays well with other programs. I've tried Agenda Fusion, another popular PIM, but it hammers the graphics subsystem in the X50v whenever it runs, forcing a soft reset to get other graphics programs to work after AF exits. YMMV.
I haven't had any alarm issues with WM2003SE. I think that 2003SE may have solved the problems. However, if you are concerned, try running Wakeup Tweak. It supposedly cleans up any alarm or calendar issues. I also run SKTools regularly, which keeps my device cleaned up. That was the first PPC program I registered and I still live by it.
I'm assuming that you've visited my PPC software page to see my comments on the various programs that I've used. It may provide a helpful guide. And of course you can always find me here.