In short the rough overview is this:
6 points
- 10 Skinks: solely usefull as fodder for an emergency screen or to grab an objective (10 skinks are simply never going to do any damage). However, noone else is quite as good at being fodder and standing on objectives. Just don't count them on actually doing anything other than standing around and looking pretty on an objective.
- Razordon: good shooting also nice for discouraging a charge, bonus points if you can put em in a bottleneck somewhere.
- Salamander: Decent shooting, but the razordon will probably perform better.
- Handlers: mostly pointless
12 points:
- 10 warriors: basicly pointless
- oldblood: basicly pointless
- priest & starpriest: usefull to replace a fallen version of the hero, or for arcane vassal, otherwise kinda pointless
- Scar-vet on cold one: usefull for replacing a fallen version, kind of amazing if you can dump him near some Knights and can get the command ability seemingly out of nowhere. One of the few summons that can make the charge as well.
- Sunblood: underwhelming
- Terradons: decent enough, provided they can live long enough to drop their boulders
- 5 guard: if they won't be subjected to mortal wounds, halfway decent. Good even if you can buff em up defensivly. otherwise pointless
- 5 Knights: decent-ish, but don't do anything well enough to really warrant a summon. Skinks are better fodder, our big dino's are better for dealing damage.
- Eterinity warden: good for replacing a fallen warden
- chameleon skinks:again, decent-ish, but not particularly outstanding in any way unless you're facing daemons.
- rippers: decent if they can live long enough to fight near a bloattoad, otherwise fairly pointless
18 points:
- Troglodon: amazingly cost-efficient, one of the few summons that can actually make the charge. Big enough to be scary, small enough to not really care if he dies.
- Starseer: currently basicly pointless summoned or otherwise…
- 20 warriors: has some use for claiming an objective where you actually need to stand and fight (which skinks just can't..) otherwise mostly pointless.
- astrolith bearer: usefull as replacement, otherwise pointless
- Kroxigor: decent provided they are summoned in optimal conditions. Otherwise underwhelming (just like regular kroxigor really..)
- EoTG: unless you can summon him turn 1 he's probably going to be too expensive to be worthwhile
24 points:
- Big dinosaurs: they're all more than worthwhile, provided you'l actually get em in combat for a round or two. Their high cost does mean you're liable to not being able to summon em quickly enough for em to have an impact.
Caveat: some of it is situational and some of the summons that are mostly pointless can in certain situations be absolutly briljant. This is just the rough general overview.
tl:dr: skinks, razordons & troglodon are fairly amazing in basicly any situation the rest varies from decent in the right situation to basicly worthless.