Option number one for a stretch 4... We call NO during draft time and offer our non-guaranteed guys and a second for Niko - so 2 of Thabo/Jerebko/Udoh. They will want to limit their luxury tax liability... Niko hasn't exactly set the world on fire since arriving. I think it has a legit shot at happening.
Option 2... offer non-guranteeds for Wilson Chandler... same premise, but we get a first from the Nuggets (2018 or 19)
Option 3 look at FA... guys like Ariza, Mbah a Moute, Thad Young(if he declines his PO) realize they aren't traditional 4s, but 3 and D wings, Thad not real stretchy buy a playmaker that has some gravity.
Option 4 FA bargain hunting - Hit the bargain bin for an Illyasova/Casspi/Bjelica/Tolliver and pair them with Jerebko.
Don't look to the draft to fill an immediate need. If there is a good option there and he is roughly as good as other options then sure... rookies don't normally contribute. Take best fit within a talent tier.