Rodney Hood, in the calendar year 2016, has posted a TS% of 59.25%.
I took every point guard, shooting guard, and small forward in the NBA that attempt at least 12 shots per game (figuring to eliminate your "role-players, secondary guys, and glue guys", as OP puts it), and among that group, only Stephen Curry, Klay Thompson, James Harden, and Kevin Durant have a higher TS% than 59.25%.
Oddly enough, it looks like in Calendar Year 2016, among volume shooters (>12 FGA) and non-bigs, Rodney Hood (a second-year player, mind you) has been about as good of a go-to guy as you can find.
Not that outsiders would be paying attention to that sort of thing.