I think that this isn't necessarily about Vitor versus Olynyk.
Given that Green and Sullinger are going to be 2/3 of the starting front court, it matters just how complementary the other body is.
The samples sizes are small, but so far, here are the results of the three likely combinations:
Front Court pos ORtg DRtg NetRtg
JG+JS+BB 138 86.2 94.2 -8.0
JG+JS+KO 161 110.6 96.9 +13.7
JG+JS+VF 15 80.0 133.3 -53.3
For whatever Olynyk's perceived 'flaws individually, the trio of Green, Sullinger and Olynyk has at least performed well so far on both ends.
In limited sample size, of course.