I agree that the 18-55 is a solid lens. It really can produce wonderful images. If you're wanting more range and to get a tiny bit better quality (mainly in the build) than the 18-55 and stay under $300 then look at a used copy of the 28-135 f/2.5-5.6 IS, or the older 28-105 f/3.5-4.5 (this is my walkaround, has been for years, and it's a great mid-grade lens).
However, I'm of the mindset that you shouldn't buy a lens if you don't know what you want. Or even why you're buying it. Because what works for me or someone else might not work for you and then that money was wasted because you have a lens you don't care for. So why specifically is it that you want a new lens? What do you hope to gain from it? What do you want to do with it?