It just seems like you're waiting for someone to say it's ok. Since everyone that's responded said you should keep the Dino Jr, and then you post asking AGAIN.
So here's your OK from someone you don't know, that won't be doing the trade so won't be benefitting from your decision. Go Ahead and make the trade if you find someone willing to take it. Don't add any cash. Just do a straight trade.
Since you don't like the Purple and Silver maybe you'll be happy with the Black/Red and Black/Royal.
edit: Let me be clear I'm not trying to be a hater, I just want to let you know that it's OK, and while people will probably tell you that you made the wrong choice only you have to be happy with the shoes you got out of the deal.