I like Blake all right, especially for a middle name. It's not really trneyd, so it goes just fine with Robert. However, I went to high school with a Blake whose last name was Roberts or Robertson, I don't remember which, so that combo is kind of associated with him. Sad to say, he was kind of a dim bulb and some people called him Blake the Flake.
The trouble with z names is a lot of hte time they remind me of Colonel Klink on Hogan's Heroes, the old WWII POW show. He always pronounced his s's like z, so Zaltene sounds like him talking about saltine crackers, Zindi like him talking to Cindy and Zabrina is what he'd say if we introduced him to our Sabrina Fair. lol
Zephyr is a nice wor,d but I'd never think it a good idea for a name, because it sounds like to me like a good name for a room deodorizer.And when I said Zdenka out loud, the first kthing that came to my mind was stinker. I can see kids mangling that one pretty bad. The other z names are, I guess, all right, though not my style at all.