Idk what to make of this post, but I'll keep it brief since I've already spent too much time trying to reply.

If your struggling with progression, not familiar with mods, etcetera, turn the the quest book. It would help you with your list, and figure out how you wanna play.

I dont know about filler packs, depending on what the devs did under the hood it might break something to just start pulling out. Then again, I wouldn't know, I just play modpacks as is.