If the Croc becomes something you can remotely call a generalist, it doesn't have to be such a wiper; we can maybe cut flamer damage by half of what it currently is.
The idea is that the main gun should double-time it to make up for lacklustre flamer damage. Since gun accuracy, generally, sucks while chasing, the Croc is no longer crazy good.
Then you should decrease it's health too. This thing can take fire from an entire army and still limp away and come back 2 minutes later fully repaired and vetted up too. It already can deal damage to tanks and penetrate them, mediums above all easily.