Interesting topic. Personally, I would feel more comfortable with risking long-term assets on a potential short-term rental once the team is a little more established (WCF) as there is a greater league-wide stigma surrounding Utah as a FA destination imo. OKC has had more recent success & Westbrook is a bigger star than Mitchell (currently).
A big reason I believe we would be better off letting the core develop/grow together for an additional year or 2 is my trust in the team culture. This past season has convinced me that this team may not necessarily need a 3rd star to contend (although actually winning a championship might be a different story) due to our system/style of play/DM & Gobert/etc.
Our core is already competitive & only going to improve as LBJ/GSW/etc continue to age. They're also young enough that imo it would make the most sense to focus on maintaining long-term flexibility unless the perfect situation happens to present itself.
This team (& DM's pull) still needs another year or 2 to grow before taking this type of gamble imo. With 2 young stars, a solid collection of young complimentary pieces, & time on his side, DL can afford to sit back & get a better read on the roster/league before attempting to add that final piece to push this team into contention.