It can be a bit difficult to get an exact value for an item for some attributes. Since loot is mostly random, level-scaling makes it easier than inputting manual values for some things. You can see what modifiers for different items take what kind of values in the Modifiers.txt file in Generated/Structure folder. So you can see that Movement on armor is a Penalty Qualifier (-10 to 10, whole numbers that are level-mapped) and that Initiative is a ConstantInt (essentially any whole number, not sure about negatives, number comes out as what you see.) You can see in the ValueLists file what values are appropriate for each type of modifier (e.g., all available attributeflags, like Crippledimmunity and Unrepairable, that you can put on armor).
I don't think you can modify the list to add or change stuff, but I might try again.
