Did you change the WiFi sleep options in the WiFi menu? When it's set to sleep when the screen shuts off, it can cause issues. It always screws my WiFi up when I leave it set to sleep. You can check this if you go to the WiFi menu and press the menu button and select advanced.
And I'm going to plug Leslie Ann's Harmonia 2 Rom here, I love the feel of it, and the ability to modify it how you please.
I use a combination of an apps to sd script, Holo launcher, the ics mdpi theme, and smart keyboard to make my optimus perfect.
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