The Jazz currently do not have a #1 option on offense. To be honest, they don't really have a #2 option either. They're hoping to acquire those guys at or near the top of the next two drafts, since these are relatively strong draft classes. (Hence, they are "tanking" to acquire those picks.) Guys like Flagg, Harper, Kasparas, Tre Johnson, maybe Jeremiah Fears, AJ Dybantsa, Cam Boozer, Darryn Peterson, etc. need to come in and play those main roles. Another possibility is to draft the #1 guy and try to swing a trade for the #2 guy, but that also takes some luck and happenstance, while Utah has not been a top-tier trade destination for star players.
If the Jazz (as currently constituted) want to make deep playoff runs, then Lauri essentially becomes the Jazz's #3 option, Walker becomes the 4th option, and they can then play Collins, Keyonte or possibly Brice as their 5th starter, with the other two of those three players coming off the bench. The Jazz have been running their offense through Sexton and Clarkson as a stopgap in the meantime.