So i just got the game on PS4 last week and i just beated the recollections mode and started the CAC mode. Can someone help me with a few questions?

1- I been wondering what are the best generic skills and how to unlock them?
2- Is there a better kagune to use for ghouls or quinx(PVE mostly right now)? And quinques too? If someone can also tell me the ways to unlock them, would be good 
3- I also noticed some achievements need to clear the campaign "X" times, so i been wondering if this c

• Tactical Roll (Level 3)
  

- This skill allows your weapon to automatically reload within a roll, however if a certain character is using a level 3 version they can provide damage to the opponent. If the opponent HP is low enough you might get a kill with the skill!

- Characters that have Tactical Roll (Level 3) 

• Klei

If you use a skill (Medkit for example) you would think that if you used it again it would refresh the duration, however this does not happen.

For some reason it doesn't effect the skill duration so if you use a certain skill and re-use it before the effect is over you may end up in combat while the effect is not active!

You can see what buffs/debuffs are in effect right next to your weapon icon bar.

Skill that you have to wait until effect is done

In many games, Immobilizing means just "being unable to move" which means it allows attacking or using skills. However, immobilizing means differently in Eternal Return. 

In Eternal Return, immobilizing is triggered by any kinds of CCs that makes enemy being unable to move either short or long time. For example, root, stun, knockback, knockdown are all considered to make immobilizing effect, while all of them except root also make the target unable to attack or use skill.

Thay's why so man