So several questions in no particular order.
1) When using progression points to add a trait, are you still limited to the 0-X from when you made the base model?
2) I have not looked at all the five factions, but from what I have seen so far there is no way to make a small model. Is this a case of based on model size you just say it is a small model, as I can also not see any buff it gets for being small?
3) If I have a trait/natural weapon or armor that is higher than my properties level does the model not get it at all or is it just caped at the properties level?
This is all for now, but I am sure there will be more as we get more into this game. Thank you.
Adding on to Ravens answers for number 1. Just to make certain the question is answered.
When adding a Class Trait through progression, each class has its maximum number of class traits allowed.
As for Faction Traits, there is no maximum. Although each trait your faction has raises your minimum point cost.
You can also replace traits when taking new ones. You just have to maintain any prerequisites for other traits.
2 and 3 are covered above.