I'm mapping interchange frequency in Salt Lake and Utah County, to determine if another interchange is needed at the Point of the Mountain. (The answer is no).
Most interchanges are 2 miles apart, or less. There are a number of gaps (20th East and I-80, 5400 South and I-215) but mostly the 'buffer' overlaps, indicating that we likely have too many interchanges. Utah County has some gaps like might bear an interchange, like 900 N. in Lehi and I-15, or the Westview Industrial Park. But the BIG gap is between the Provo Center Street and University Parkway. They are over 18,000 feet (~3.5 miles) apart. Which is a big deal, because BYU is due east of that point...
An interchange at about Provo 1500 N. seems to be missing. A split interchange, connecting on 1640 N. to the west, and 1480 N. to the East, would do a lot to fix that. You could drive from I-15 along 1460 N. to Grandview Lane to Columbia Lane to Bulldog Boulevard and into BYU, passing the Utah Valley Hospital along the way. (820 N. would be a viable alternative).
Ideally, it could just be built as a HOT/HOV ramp. Satisfy transportation demand without unleasing a horde of vehicles on the street.