Price: There's no rule. It depends on what's in your pack. Keep in mind if you price something at $30, you can always discount it to $15. If you price something at $1 you can't discount it - well people do, but itch.io has a minimum payment of $1 - so any price below that is nonsense.
Followers: It's not important why they follow you - they did, and if they don't like something they can unfollow you. Just keep in mind that just because you have x amount of followers doesn't mean that many people will go look at anything you post.
You might consider placing your assets in more stores, especially if it's designed for gaming in the Asset stores of the different software, like Unity Asset Store,
Sales - I think for every person who has done well, there are probably 1000 people who've sold nothing. There might also be something to do with the circle of friends or network the person is in or they made something that captured the imagination. But that shouldn't stop you from trying.
I wish you the best of luck!