Carbon steel used to be a better general steel category for cutlery because it took a better edge, held it longer, and was easier to sharpen. The same is not necessarily true today. Steels like AEB-L, CPM154, etc. are great stainless steels.
Today, personally, I wouldn't pick based on carbon versus stainless alone. If I wanted a carbon knife, it would be because I wanted to try that particular carbon.....or because I wanted a knife that developed a patina. Same holds true to pick a stainless except that I would want a knife that didn't develop a patina.
wa versus western is entirely personal. Some, like me, enjoy both. Others develop strong preferences for one over the other.
A couple of my favorites:
Incredible semi-stainless steel knife with a western handle. Not crazy thin, but still very thin.
Kohetsu AS 240mm:http://www.chefknivestogo.com/rikoaosu24gy.html
Carbon steel core, clad in stainless....very thin knife, wa handled.
Fujiwara makes good budget knives in both stainless and carbon:http://www.chefknivestogo.com/fujiwara-knives.html
Hope that helps a bit. Let us know if you have any further questions.