why don't you want winterboard?
It doesn't slow down mine, and you could just use winterboard to get the weather on your Lockscreenslows down the phone and I don't really care about changing the theme.
I'm currently using Homescreen 2.0, and it's working okay. But you're going to need Winterboard to use it. I've also tried Wbapp which comes with a Weather Widget. You might be able to use that one without Winterboard. You can also use the widget on your homescreen.