Ok, let us take a look…
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Both Mike and Jack-Jack are nice fantastic damage dealers, yet Mike has more HP and scaring, while Jack-Jack damages over time. Between those two I would choose Mike. Yet you also got Violet, whose supportive skills makes her team very hard to defeat. Of all three, I would take Violet.
Nothing to say here actually, it gets updated every week and has no specific characters. Just take chips of those you upgrade.
Harder to say, all three may be useful. Aladdin has pretty good damage, Jessie has nice self-healing, bug Judy is not that risky as they are. Yoh see, Al and Jess have skills that include jumping right into the enemy team and striking everyone, but they also get thr enemy’s attention. Sorry, can’t be sure here.
This introduces three good characters BTW. But the problem with Sulley is that he is useless against normal damage dealers like Jack Sparrow, Barbossa or Merida. When those are introduced to your server, Sulley will become your weak point. WALL-E is great at controlling enemies, while Moana has great self-healing. I would recommend choosing from those two, starting with Moana.
Of all those you called Dash and Finnick are the best choice IMO. Dash deals some good damage, while Finnick slows down his foes. All other characters will get “better versions” in the future(Or now).
Vanellope and Elastigirl-those are not bad damagers, but some others are more powerful(Merida, Nick).
Ralph-well, almost any tank with the exception of Felix.
Frozone-all other freezers(WALL-E, Olaf, Elsa).
Mr. I-he has good HP, but nothing else. Shields(Bogo, Baymax) and self-healing/reviving(Sulley, Sally, Hades, Olaf, Goofy) are important for tanks. Oh, and Shank. She is just a tough one.
Well, that’s what I can say. Others can improve my words or add something, as we all have different strategies.