There just aren't many realistic options for upgrading 3B this offseason. The easiest 3B solution for the Brewers would be extending Adames then moving him to 3B. HIs defense likely plays better at 3B than SS because his range to his left is his defensive weakpoint. His bat is definitely good enough to be a 3B and he becomes a plus baserunner as a 3B.
We can move Urias to 2B. Brosseau can platoon with Rowdy at 1B. Wong can either have his option declined, picked up and traded, or picked up and splitting his time between 2B and DH against RHP. We would likely need to sign a short term stop gap at SS (maybe Jose Iglesias on 1/2.5) to split time with Turang at SS and get the AB's against LHP at SS.
Against LHP the infield would be Adames, Iglesias, Urias, Brosseau. Against RHP the infield would be Adames, Turang/Iglesias, Wong/Urias, Tellez.
This way we have 3B (a weak position in our farm system) locked up long term and it gives the Brewers a year to decide whether Turang is good enough to be an everyday SS.