Wow! I like this list
Let me preface this by saying I do not play lizardmen, but I did purchase the codex, read it obsessively, and read a lot of army lists

. Yours does not look like any I've seen, which is pretty cool!
Why have all 3 razordons as one unit? Similar question for the Terradons, could you afford one more and split them into two separate units (to go
MSU-style even more)? It seems like these squads would be more effective as separate units.
Also, you weren't tempted by the Blade of Realities? I have a feeling the build on your Carnosaur is more competitive, but that other weapon is incredibly cool

. Since the Carnosaur is not a large target, what are you going to do with it to try to hide it / get it into combat?
The main downfall of this list I think would be someone getting your carnosaur into combat too soon, and then leading it off the table, since it's the only
CC punch you have other than the steggies. I'd love to hear what your planned strategy is with this list!