Few issues.
1. Heyward produced an OPS+ of 115 in 2015
2. OPS+ is pretty worthless of a stat. Realize that OPS is a flawed stat. There was a time it was the best stat we had, but then the algorithms improved. But there's a number of issues. First you're cramming together 2 numbers that have different denominators. (SLG is TB/AB OBP is H+B+HPB/PA) second is that it double counts the base hit as it's calculated. Also it deals with the core issues of the stat which is the run value of every input into the stats.
Using a better stay like wRC+ you see Heyward is a net positive right now.