If the Bucks, for example, were sitting on a very low win total heading toward the trade deadline and they offered us Henson, Antentokounpo, Caron Butler's expiring contract, and two 1sts (2014, 2016), I'd probably seriously consider that offer.
I think whatever team is trading for Rondo would have to be a team with some nice talent already on board, that is interested in being competitive ASAP, that doesn't already have a really good starting point guard, and that is having an unexpected down year.
I doubt that you're going to get a 5 star prospect for Rondo. More likely, you could get a couple of 3 star prospects and a future 1st or two. If one of those 1sts is projected to be a top 10 pick this year, I'd pull the trigger.
Another example:
The Kings, with new ownership, want to be competitive again ASAP.
They offer Ben McLemore, Isaiah Thomas (RFA this summer), Jason Thompson, and their 1st round pick this year.
In return, they want Rondo, Bradley, and one of the Nets' 1sts.
That would be very difficult to pass up.