Quick opinionated chart rating each assist for each character by four different general situations; Offense, Defense, Neutral, Combo

Offense: Calling assist after establishing and offensive positions. Example, after a blocksting

Defense: Calling assist to counter opponents offense. Example, after or before blocking an attack

Neutral: Calling assist while neither player is in an offensive or defensive position. Example, there is a considerable amount of space between both players

Combo: Calling assist during a combo to either extend or reset the combo. Example, after putting the opponent into hitstun call assist

Grade system: I will be using a C through S system with each letter representing a point system. A + will equal half a point and will be used for when an assist is stronger than others in the same tier

(3 points) S: You should be trying to force the situation to call the assist in your overall gameplan

(2 points) A: This assist if excellent for this situation

(1 point) B: You can use this assist in this situation but use a better option if available

(0 points) C: I would not use this assist here if I were you but good luck anyway

It should be noted that all of this is opinionated based on my own play and is not the end all be all.

Some assists can better make up for a character's weaknesses and finding the right assist for your character is half the fun.

*This assist has the issue of only being available half the time but the access to raw tag it enables is worth the downside