Red cabbage in an egg roll or gyoza dumpling would truly suck. I also like making crack-slaw and traditional cole slaw.....in all cases, green would be my choice based on tradition.
Now...Red cabbage varieties typically grow in smaller heads, therefore it's more expensive per pound due to the amount of waste when you cut out the stalk. I'm going to venture to say that that counts against it further. I prefer green to red....but don't dislike anything about red....it would likely make a decent substitute.
You said it yourself though OP....2 parts green to 1 part red. You may like red cabbage more, but you aren't going 100% red. Perhaps it'd overpower the dish with more cabbage flavor than you want? I really like cabbage, but it's typically a filler vegetable in my soups and filler in the other foods I make. I even like cutting it into wedges in BBQ season, sprinkling with cajun seasoning, wrapping it in foil/olive oil and smoking it with my pork roasts...