Get the best package for Lauri, if the intention is not to make this team drastically better via trades and FA on becoming summer. For me, it makes no sense to max, or near to max Lauri, before we will see this team having one playoffs series at least with that core. And for Lauri, he either needs to not think his career but his family, to extend the contract on becoming summer.
If we are not seeing Lauri traded on this season though, I am kind of convinced he has given a verbal agreement to extend with the team, even if things look as bad next season. It seems Buddy Hield might make the playoffs this season, making Lauri the longest streak of no post-season from active players.
Also, considering his brand of offense, his late prime might not be as long than someone who are less relied on their athleticism and huge amount of work to fight themselves open as the off-ball threats. Calculating risk factors and the timeline of the team, and how the western up and coming teams are way ahead in their build, and adding the personal goals Lauri might be having... Might be the best to grab 3-4 firsts and decent young projects for him, and look ahead into late 2020s to be relevant again.