I am trying to determine the relative strength or potency of flavour that comes from different spices and herbs. I often find myself lost when trying to blend recipes since certain spices can be quite potent and it is easy to ruin a recipe with a powerful spice from another recipe. The best solution is to divide the weight of the spices by the total weight of the recipe in order to apply a similar ratio in my own recipe, but this is extremely cumbersome.
A simple way to address this issue would be to add spices based on their relative potency. For example: if I have 10g of dried thyme and I want to add nutmeg to the recipe, and I know that nutmeg is roughly 10x more potent (just a guess!), then I can add 1g of nutmeg and I can be assured I haven't ruined the recipe.
I know spices vary in their flavourfulness based on their age, different parts of the world, how they're processed, etc., but there's also no doubt that some are far more potent than others. I know the relative potency of certain herbs and spices offhand, but there are many others I am ignorant about.
Is there a list or resource that ranks the potency of herbs or spices? Some numerical indices would be fantastic, but even just categorization (e.g., very strong, strong, moderate, weak, very weak) would be helpful.