If your doing it for the attractions, I’d imagine you know what those attractions are, and that’s your answer. It also depends on how big your group is, how old everyone is, etc (ie. LEGO land is a huge disappointment for older kids, if you are expecting anything even close to Disneyland or alike). Mormon battalion is ok if you have never done it. Old town is ok for half day if you’ve never done it. Honestly, I’m more of a beach person, and we live in south OC, and still every vacation we go on is a coastal destination with little if any “attractions” besides the the beach, local restaurants, and local shopping.