Hey man, I lived in SLC for a year (actually Murray, but it's part of the Greater SLC area).
So here are some things I can recommend...
1 - Sugarhouse Coffee, best coffee in SLC. Filled with leftists and hippies, but order the Cuban Revolver and you'll be wired for the rest of the trip.
2 - Fort Douglas Miltiary Museum, I used to intern here. There's a lot of cool shit like legit iron crosses, and a vehicle park with sherman tanks and willy jeeps. Also they have a STG-44 in mint condition.
3 - Day trip to Park City. Walk up and down the Main Street. Buy an overpriced beer. Honestly, the drive in is more worth than the actual town. The town itself is real expensive, but the landscape around it is beautiful.
4 - Temple Square, the holy Mecca of Mormonism on Earth. You can't go into the temple because you're a filthy gentile, but you can look at it.
5 - Eagle Gate, right next to Temple Square. The gate itself is just a piece of metal over an intersection. Next to it is a house that was the home of one of the original settlers. Some bigwig. Never been, because I am a filthy gentile.
6 - This Is the Place Park, this is like a little village/open air museum that's filled with mormons petting goats and pretending it's 1850. I would not recommend it. I took a mormon girl here for a date and she loved it, but I just kept trying to find a place that sold beer. Spoiler alert, there is none.
7 - Ensign Peak, is a hill overlooking the entirety of Salt Lake City. Honestly, if you do anything on this list walk up Ensign Peak. In the very least you will be able to take awesome pictures of the city. It's the hill from which the original mormons organized the entire layout of the city.