You should google mill work for your area, or go to a 'better' lumber yard that has a show room - get some ideas. Maybe you want some flat panel shaker type doors. Also you could use a two part trim - a trim board with another piece on the edge.

Anything but clamshell.

The purists will tell you clamshell or ranch. I put in what I like.

I'm torn between being a purist and figuring out what I like. Kitchen cabinets are part of my dilemma too.

Clamshell in nicer wood you mean like in natural stain color maybe?

I'm thinkning simple square trim is the way to go.

Yeah, stained wood. If you're painting it then it doesn't matter. My '50s house has a clamshell-ish mahogany trim which we couldn't replicate for our addition so we snuck in cherry.

Simple square might be too simple. But you can probably find something more interesting than square and less dated than clamshell. I'd just want to avoid tall moldings, or anything that would work in a mcmansion or a colonial...embrace the classic ranch. Be sleek!

You might want to run it by the decorating forum. http://ths.gardenweb.com/forums/decor