Also, if you're going for 2 shadowstrikes, you might wanne swap out some skinks for chameleons to up the annoyance factor.
And why are you using 2 starpriests and then a priest as general? Seems a bit many priests (especially considering how weak they are apart from their 1 supporting trick).
Other than that, the idea of 2 shadowstrikes could quite easily work. The flyers are your fighters, skinks as your fodder & a 40 man unit is actually effective. Get some chameleons to further threaten and annoy key-targets.
Let's see, an example list:
Shadowstrike 120
Skink Starpriest/priest 80
-Artefact
40x Skinks 200
40x Skinks 200
3x Ripperdactyls 140
Shadowstrike 120
Skink Starpriest/priest 80
-Artefact
10x Chameleons Skinks 240
40x Skinks 200
3x Terradons 120
Comes to exactly 1500 points.
You have a crapton of wounds with the amount of skinks, chameleons can jump around annoying the hell out of enemies. Also, with a 120 skinks you can now put out a 120 attacks, at 3+/5+/-/1 re-rolling 1's to wound and to hit resulting in eh, 32 wounds if you'd make em all hit the designated target by your pries/starpriest. If your enemy isn't using something ridiculously sturdy you might be quite succesfull using ranged attacks and weary fighter.
I would say that the 3 times 40 skinks are basicly mandatory for this setup. They're extremely cheap, actually put out a decent amount of attacks, fullfill your battleline requirements, provide you with the wounds required to not just be swept away after 1 turn. And the psychological effect of a 120 of the buggers runningaround probably helps as well.
The last unit of skinks is up for debate. You can either bring some chameleons, another block of 40 skinks to get to a whopping 160 models. Or simply take 10 skinks to spend points somwhere else.
As for terradons & ripperdactyls. Personally I'd guess that terradons might be a tad more succesfull in this particular setup. They have some extra ranged attacks which makes them a tad more reliable. And they don't have as much of a bullseye painted on them. If your opponent fears rippers enough he'l just unload on them immeadiatly and ignore your skinks. If he doesn't fear terradons that much he might get triggered by the massive amount of skinks more easily, allowing your terradons an extra round or two of unloading their stuff which ultimatly might be better.
Now at 1500 this'l mostly just be a silly list. However, at 2000 or 2500 points this might actually start to get good. Fill those remaining 500-1000 points with some behemoths and an actual decent general and it looks like a very decent list. The sheer amount of skinks makes for a nice core functioning as both fodder and to just bury your opponent in attacks, the priest/starpriest provide decent support. The flyers can dish out a reasonable amount of damage while not being terribly squishy themselfs. Get in a behemoth or two and you have a functional army.