Or Turner, shifting Turner to 2B. IIRC, Kieboom grades as a better defensive SS
I don't believe that to be true. While I don't know the grades at draft time, Turner has always been expected to stick at short. Kieboom has always been expected to move off the position. I think hes done well enough to stick, but I don't think he graded out better than Trea.
I wouldn't rule anything out, but I think Trea is better suited at short than Kieboom.