I don't really agree that the Jansen hit ruined him. That was late in the 06/07 season, but he was basically every bit as good in 07/08 as he was in 06/07. His decline was slow and steady, TONNES of players drop off sharply in their early 30s, it's the exception, not the rule, for players to still be effective in their late 30s.
We should also remember that Kaberle in his prime feasted on the PP. His huge point season was in 05/06, the first year after the lockout, when there were an INSANE number of PPs called, and virtually all players who got a lot of PP time put up career numbers. Kaberle had 67 points that year, but an insane 51 of them were on the PP. In no other year did he have more than 30 PP points, it was clearly unsustainable production for him, and had A LOT to do with how the league was being reffed back then. He was really more of a 50ish point guy during his prime, and mostly put up that nuts year due to the massive number of PPs league wide in 05/06.
In his prime Kaberle was an elite skater, passer and puck mover, but he was also always very soft, very easily outmuscled in his own end, and he was never much of a shooter. As time went on his weaknesses became a bit worse, and his strengths less strong, so he slowly degraded into a liability. He was never a real all-around player though, he was always a guy who was elite in certain areas, and pretty weak in other areas.