I do agree with the Jaguar Charm being less useful. It's great as a surprise the first time I pulled it, but once they took out the other spell casters, it felt like I was just using it to hope they'd roll snake eyes on the dispel attempt.
I've considered an idea like that with the Saurus. Has equal ups and downs. Will probably try it out in the next fight.
Cold Ones are around for a fast moving powerhouse unit. I am curious as to how Terradons would handle, but they seem a bit too fragile for my liking if faced against a gun/bow line of any kind. Again, a play test will probably be happening sometime soon.
I just really like the Rod of Storms. Granted yes, it's a one-shot wonder, but it's proven useful against WoC and warmachine crews. That and with the exception of the DE player in my group, not much really happens in the magic phase to warrant a 2nd Dispel scroll.