Hi John,
I like the idea of the castle, but I think with the shield there is too much going on. I would like to see something with just the castle, no shield. I would also like to see some other colors than green.
I still like the shield idea, but I think having the word "noble" and a symbol in the shield as well is too busy/too much going on.
Please feel free to play around with the location of things. It doesn't have to be the symbol on the left, name on the right kind of thing.