They do but the more attractive free agency comes next year. Obviously Curry will not move anywhere despite being UFA but even Westbrook might be available if Durant contemplates leaving and they have another upsetting season. Then you have Griffin, Lowry, Millsap and Hayward who will more than likely opt out to seek better deals, some RFAs who might not be matched like Schroder, Noel, Adams or maybe even CJ plus lucrative UFAs like Iguodala, Ibaka, Evans and Teague. Some teams might be willing to keep their money until next season which is what Cuban has recently suggested too.
Celtics are the team that I fully expect to be properly awesome from 2017-18 onwards. They have immense amount of cap space ($40M+ this year I think) and will probably be going strong for Durant and Horford this year plus 1-2 stars next year. They're shopping their #3 pick this year and could possibly get Butler for it (rumoured package also including Smart who will become dispensable plus Amir Johnson to clear cap space).
Ingram had a good workout with Sixers yesterday. I'd say it's 60/40 in Simmons favour in regards to who goes first this draft.