Jost has already proven he can skate well enough to play center, and he hasn't even had another off season to improve his stride. The talent is there, the shot is there, the passing is there, the vision is there. He's already one of the best defensive forwards on the team, and has become a great puck thief. He's just having a hard time putting it all together offensively with linemates that don't suit him.
If he can't put together his offensive game, he'll stay a much less effective player. He's still young though, people have been trying to define his ceiling, and kind of player he's capable of being, since day one. It's still too early, and I think we need to see him more with better linemates to know for sure what he's capable of.
When he's with smaller quicker guys like Kerfoot, they like to play off the rush, and that doesn't suit him. When he's with Calvert, Wilson, and Bourque like he's been lately, they can help him down low, but don't have the skill or smarts to hit Jost with passes when he's open. They also don't come out of the cycle and put themselves in the soft spots to receive passes for good scoring chances. When they do they miss the net or shoot into the goalies chest.
By his own admission Jost likes to play a down low cycle game, and this is why he looked so much better with Landy. Landy can help him down low on the cycle, he can help him defensively, he can find the soft spots coming out of the cycle to receive passes, and he can hit Jost with good passes himself.
Without someone like this Jost tries to do too much on his own, and he doesn't have the physical attributes to do that. He needs good line mates, and they need to play like a line, not like individual skill players. It's just one of the many reasons why this team needs a gritty middle six winger that's in between Landy and Calvert in skill.