Serge Ibaka went from one of the, if not the primary rim-protector in the league, blocking everything in sight, as well as being a legitimate threat to score whenever he got the ball during his time in Oklahoma City. However, since being traded to the Magic for a package including Victor Oladipo, his production has dropped steeply on both ends of the court.
He can occasionally shoot from mid-range, can rarely shoot from beyond the arc, and misses too many layups to be a true weapon on offense. On the defensive end, he's averaging almost an entire block-per-game less than he was in his final season with the Thunder in OKC (2015-16), and actually managed to drop more than a full block-per-game from the 2014-15 season to this most recent season.
The solution to his problems is really quite simple, and is not something that Serge himself can do, but rather something that the Raptors coaching staff will hopefully do for Serge to see his stats and his effect on the game increase. All Nick Nurse needs to do is give Ibaka either the starting job at center in a small-ball lineup, or a backup position at center in a small-ball lineup. Just give the man some minutes at center! If Ibaka was playing the 5-spot, he would easily get those blocks back up, seeing as he would have more of a defensive presence in the paint than he was having at the 4, and he would also be able to get more touches down low on offense, where he should be able to absolutely bully other small-ball centers. If it's a traditional, 7-foot center that he's playing against, then he can get the ball outside and either shoot or drive depending on how much space the defender gives him.