I really, really don't think that the Jazz are going to trade Exum. He's still the player on the Jazz, next to Rudy, with the biggest upside and the highest potential ceiling and, from the sound of things, it's beginning to click for him. In fact, I think that the acquisition of Rubio is actually a direct complement to Exum - they know that if Dante shows major progress this year, it's going to lift his price next year in free agency. It appears that the Jazz are trying to do whatever they can to get under the cap this year so that they can go into luxury cap territory next year without penalty - assuming Hayward re-signs.
If Hayward bolts, the Jazz frankly need both Exum and Hood to continue development in order to make up for the loss - their development, along with Rudy and Mitchell, will be the only thing that has the potential to spare the team from entering the 8th-seed treadmill game.
The one to watch, in my opinion, is Favors. Hard for me to imagine that they'd bring in Rubio and the issue that both he and Dante (for now) have with floor-spacing and match them with Favors in the front court. Going to be a fascinating couple of days.