Not make the suns better right now IMO.
If you’re starting a team from scratch you may pick Luka depending on how you want to run things.
I’ll say this tho… if my team is down 10 I definitely want Booker. Luka in a deficit turns into awful hero/iso ball and it can be awesome or terrible depending on how hot he is. In this series it’s been ugly when he forgets to share the ball and tried too hard to carry his team.