What Can I Do with this Design?

I am still not happy with the design of this website. I love the front page and see no need to change it, but these "inner" pages seem bland and unfinished to me.

I am not a designer. I have never claimed to be a designer. I am a programmer, and it shows!

Andrei Herasimchuk has made me consider, with a critical eye, the typography of the site. Having thought about Andrei's comments, I have come to agree with him that Trebuchet will not stand the test of time, despite my previous advocacy.

There are some truly beautiful websites out there and I want the Urban Mainframe to be of the same ilk. But, to be honest, I don't know where to start.

So I am asking you, dear reader. What should I do with the design? Do any of you have any suggestions? Are there any discarded templates out there that I could adapt for this site?

Please don't misunderstand me - I am not looking for free web design. I am looking for ideas, inspiration, tips... a gentle nudge in the right direction.

Or, should I leave well alone? This website has already gone through three redesigns in just 18 months, do I need to make my visitors "learn" its interface all over again?