I know you are considering a wide angle lens. I too have a gh1, and my favorite lens is the Oly 45mm f1.8. It is a fabulous lens. The Panasonic 14mm f2.5 is considered a wide angle great lens, though I do not own it, it would be no wider than the wide end of your kit lens, but is an f2.5 making a more versatile lens, and is also a tiny pancake.
For $700 you could probably get both.
the Oly 45mm will breath new life into that Gh1
I am currently saving for the Panasonic 25mm f1.4, considered to be one of the best MFT lenses.
yes move on from your kit lens, there are a lot of great options.