Weapon Ranks versus Attack Points

[Stormchaser]

I have the same dilemma/questions:
1. If you already have a more powerful weapon than the Sword, Doll, Gun, Etc. upgraded weapon offered in the quest, is it really worth it running all over the place trying to get the upgrade?
The answer to this one is probably in POTC 101 Answer: It depends on your playing style and goal. (Yes & NO) just depends on your mission.

2. Should I dump Pirate blade for X rare weapon with better attack?
3. Can I at least dump the lower level quest doll once I have the higher level quest doll, or other weapon.

Now one sort of related question: Can someone explain the impact of "Low Critical Strike" on some weapons?