Carnal/Heroic upgrades

[bcombs]

So I just started the game on Thane difficulty today. I decided to do the heroic upgrades/index on this playthrough. Then I'll do carnal for legendary.

Anyway, I'm near the end of Episode 5 and I only have 9 Heroic upgrade things.
I know I need 56 to fully max it out. So my question is, is there a certain amount I should be aiming for on each level? Is it hard to get 56 by the end of the game?
It seems that way to me because every time it adds up my heroic kills, heroic storms, thane kills, etc, I end up getting only one upgrade.

[M85A21]

You will only get one Heroic Symbol at those stages.
But if you kill a boss on Heroic Storm you will get 7 I think.
THen everytime you go to Grendals Mothers lair and she tries to seduce you last about 2 minutes or more and you will get 9 Heroic Upgrades.

[Chrome30]

The key to it is making sure you last 2 min on the temptress part. Then make sure you finish bosses and such off in heroic. You should be maxed right after the last tempting, if done correctly. If not then beat Hela Heroic. Good luck!