Is there a spice ratio per lb of Fried Chicken?

The amount of spice is a matter of personal preference. Some people might like more spices, others might find that amount too much. It's really your call.

I recommend that you find a reliable recipe from a proven source (a workhorse deadtrees cookbook like Fannie Farmer or Joy of Cooking or a carefully curated website like Serious Eats) and look at their recommendation.

You will need to think carefully about your own tastebuds and how you envision your final dish to appear on your table.

In the end, what you like is what really matters. After all, you're the one who is going to eat it, not us.

Good luck.

I searched fried chicken recipes on the site. Here are some options. Perhaps you could compare them and arrive at a variation you like. https://food52.com/recipes/search?q=fried+chicken