Well I already gave my opinion, but if you are planning on releasing it I will be more detailed. My only real gripe is systray size, 5 is just not enough for most people, I have 9 on my laptop right now, and I like to see most of them. I like the idea of the popuptop image but I think something more abstract would be better idea.

Other things to think about:
* Bar can be toggled from top, bottom, or off
* What other info will be displayed in the clock for mouseovers or left/right clicks?

That's really about it, I would probably use this theme for awhile, but I would definitely change the systray size and bar to top/toggleable for personal use.

All in all good for a first theme, I know you said you based a lot of it on other work but thats what first themes are all about. :)