If it was me, I would do everything I could to lure Butler or Kawhi. Your probably gonna end up overpaying, but that's what you do if you want a RFA. Play with the contract structure to make it harder for their teams to swallow if it seems like they wanna come here. There probably both not going anywhere, but I'd at least try hard. They're both perfect fits and have star potential. Draymond Green is a similar situation but I'd wanna be in for less money then Butler or Kawhi. Might be a little easier to get him out of GS though.
Assuming that goes nowhere, I'd still try for Khris Middleton. He's a versatile player with room to improve, the Bucks may not match on him and he's the kinda guy that would fit right into our locker room. I'd make a good run at D.Jordan too, or try and pry someone like Adams from OKC in trade cause if we can fill our hole at the 5 through FA or trade we can focus our draft assets on SF. I wanna resign Crowder because he's the perfect glue guy, and he exemplifies the kind of attitude we want here. But he's probably not a starter. Especially when this team needs a guy who can score and command attention.
If we can fill the hole at the 5 through other means, I would consider trying to trade up for Stanley Johnson. I like him the most out of the current crop. I normally go for BPA, but this year with this team I'd go BPA out of the guys who can fill one of our major holes. If we don't get a 5 by other means I'd probably try first for WCS and take Turner as a contingency plan. I really don't like Oubre.
Of course, there are a few interesting names we might be able to trade for that could do well here. Otto Porter Jr is a guy who was a top pick but his stock has really fell this season. Washington is trying to build something around the Wall/Beal backcourt so he could possibly be grabbed. Harrison Barnes is an interesting though. If GS resigns Green he could finally be expendable. He's shown some talent and he's the kind of player who won't thrive being the 4th or 5th option, but he hasn't really taken any steps forward.
Of course, if all else fails I would just take the best available 3 or 5 available in the draft , keep working the phones, and ride Turner/Crowder for the year. I think if you add any talent, regardless of position to this team , CBS will have them improve.