Interesting trade. Personally, I'm not sure the extra offense you get from Duvall in the platoon is enough of an offset from what I see as a slight step back on defense from the Inciarte CF, Acuna LF alignment. Add to that, Inciarte has been a better second half performer during his career. So I see the 2018 benefit of this move being more about depth and insurance. The cost is so low, it's probably a worthwhile move just for that.
Duvall will get paid handsomely in his first year of arbitration due to his career HR and RBI. $4m - $5m maybe? It is not out of the question he's non-tendered, but probably unlikely. In any event, Duvall should be valued as a player with very modest surplus value in 2019, and no surplus value beyond that unless he breaks out. He's at least an option to contribute in 2019 and provide some roster insurance / leverage with Markakis a free agent.
Tucker I don't see having any long-term value. He's a platoon corner OF with below average defense that's out of options. I wish him well, but think its very unlikely the Reds carry him on the 40-man this Winter. Wisler (no options remaining) and Sims (one option remaining) are reasonable lottery tickets for a team like the Reds with constant SP struggles. On the off chance they win the lottery on one of the two of them, the prize will be a cheap back-end starter with limited upside that figures to be non-tendered in the first or second year of arbitration.