The interesting thing here is that depending on which character they add, it will confirm various character upgrades as possible. Let me elaborate:
- If Min-Min, Twintelle, or Ninjara is the character, then it will confirm that spirits can become fighters.
- If Ribbon Girl is the character, then it will confirm that spirits and Mii fighter costumes can become fighters.
- If Spring Man is the fighter, then it will confirm that spirits, Mii fighter costumes, and Assist Trophies can become fighters.
This is exciting for me because there are spirits (Rayman) and assist trophies (Shovel Knight, Waluigi) who I want to be playable. If Spring Man is the character, then other assist trophies being upgraded becomes very likely, so for that reason I kind of want it to be him. However, if I'm choosing the characters for their own sake, then I'd prefer Min-Min, who I think is the character they are most likely going to pick since she is the most popular character from ARMS (plus she won that tournament thing).