For me a check on whether trade proposal is realistic is simple: does it hurt?
In this case, it does. I do not want to give up Brown or 17 Nets pick, but you have to give something of value to get value back.
Also, historically, a team that gets the best player in a trade usually wins long term.
Given all of this, I would stand behind this kind of trade.
However, if we add another non-BKN 1st to Philly and get Saric for that then the trade, from my perspective, would be much better.