1 - tough to say, but the Stygiosaur has found a solid place as a support unit. The Carnosaur has been much harder to balance, and so has swung from auto-include to useless from version to version (of the Beta stage, that is, when new versions were released every few months). On the other hand, there is a lot of desire for the Carnosaur to be useful, so you can bet that in the long run, we will end up with rules that make it worth playing.
2 - ditto
@SilverFaith . Snake Altar seems to be preferred by most players, but given that low WS is one of our weaknesses, the Sun Engine seems to me to have great synergy with a list that relies on Saurian Warriors and Caimans. My friends and I proxy freely, so I could play it either way. But every time I've played it, I've used the Sun Engine.
3 - I like the blowpipes, though the Great Bow does give some much-needed ranged strength. But with mediocre odds of hitting to begin with, I'll take 8 shots over 1.
4 - I've often played with Rhampho's, but they really require a lot of care to find the right matchup. In a lot of ways they function the same as Ripperdactyls in 8th Edition, but T9A did a recent rules...experiment?...wherein Skirmishers do not close their formation in combat. This means that a unit of Rhampho's has fewer models spread out over a wider frontage in combat, strongly negating the matchups where they were at their best before: cavalry and other elites. Even so, observe a couple of cardinal rules and they'll find some use: 1) good targets are enemies with lower Initiative. 2) good targets are the ones you marked with a frog. 3) good targets rely on armor for survivability. 4) use Skirmish and Flying movement to your advantage: negate the downsides of Frenzy by flying your Rhampho's out of harm's way, and facing away from the enemy. That way they don't have to Frenzy-check. Face them towards your target when you have set up the charge for them against a good target. 5)hit good targets in the flank.
Finally, until this Skirmish thing gets resolved, it might be worth fielding Rhampho's in a 1-wide, 3-deep formation. It's definitely not worth fielding them 3-wide.
Then again, you can play Pteradons, who don't do much in combat, only do a little shooting, but can be relied on to do what they do.
Of course, if you can convince whomever you play with to allow proxy models, too, then you can just model whatever looks better.
