I think each person has their own definition of a good web design.. heres mine ^^
-It would have to fit on most resolutions for visitor conveinience
-It would have to be easily navigational (I'll see some pople use stars or circles for their navigation, and the
only way to know where they lead to is hover over them or visit all the pages)
-Color friendly. Blinding colors like lime green with neon orange are kinda... painful.
-I personally like alot of content space, but most times thats hard to come by.
-Flexibility is always nice if your into changing things around a bit, like links.
-Originality.
-Short loading time. I know a lot of sites where they clump images into a whole, or they add mp3s to spice up the
pages. Things like that load very slowly on slow connection speeds, which often discourage the visitor, and they
leave.
-Operational. This is key, broken links or missing images/pages can get annoying.
I'm sure there are more factors, but those are usually what I look for when I look at or make web layouts.
by the way, your layout you made looks good ^^