Since the start of the 2016 season (not counting today), Grichuk has a 99 wRC+ in 1919 plate appearances.
I mean, a league average hitter with good defence is a decent player, but not someone I'd want batting anywhere near the top of the lineup, especially when his OBP is so bad.
Of course the Jays hitters are young/not established yet, so where he fits in the current lineup is debatable. If everyone is healthy, I'd say 6th is the highest I'd put him (Bo-Biggio-Vlad-Gurriel-Smoak being ahead of him).
I'm still holding out hope that he somehow breaks out next year unexpectedly like Smoak did. I remember reading they were tinkering with his swing, so maybe that might explain some of the down season, but it's not like he's going anywhere, so hope for the best.