What I want to see out of DeBrusk is to showcase his speed more. When he moves his feet and keeps his motor running high, he's a good player and helps make things happen. Some nights, he doesn't seem to skate hard, but I'll never question the kids guts. I think he mucks it up along the boards and in front of the net as hard as anyone on the team.
DeBrusk is gritty, and willing to get dirty, can't deny him that. But his primary role on this team is to score goals, or failing that to be banking points by assisting others to score. Currently he's on pace for around 40 points, which is worse than last season, and just 20 goals. It's not terrible, but it's also not good enough for a guy who's supposed to be driving the scoring on his line and is getting an average of 16 min TOI per game and some regular PP time.
I wouldn't say he's gone backwards but he's just stagnated - I can't think of a single thing he's doing better this season than he did last, except maybe his screening and work in front of the net has improved slightly. You note his speed and I agree 100% - one thing he was doing well was finding space and creating separation from opponents, but that and his touch of flair with the puck on his stick have rarely been seen this year. Instead he's becoming just another small-ish grunt player on a team that already has quite enough of them.
As I said, I don't think he's been awful and he's far from alone in fighting for form at the moment, but I feel like it's particularly frustrating with Jake because he's young, should still be developing, and has high-level talent and that rare ability to do things that make you gasp and take notice, but at present it's not really happening for him.
On the flip side, young players have their peaks and troughs and that's normal, and in mitigation he's lacked consistent line-mates all season. We're a bit over a third of the season in now, I think it's fair to give him another third or so and hopefully some more stability before giving a more firm opinion on how he's travelling. Hopefully he'll soon turn the corner and not look back.