Select Parameter Suggestions

[RagingRowen]

suborder:
The match the character/stage will appear in based on the order chosen.
Example:
The Tournament's Final Arena (ala CvS2) being selected for the final match for order=1.
Usage:
order=1, suborder=8

group:
If an opponent in arcade mode is in a group, other fighters from that group will be alongside them if it's a Team.
Example: Teams in KOF Arcade Modes.
Usage:
Kyo, group=Japan
Benimaru, group=Japan
Ryu, group=Ansatsuken
Ken, group=Ansatsuken

[K4thos]

Arcade paths feature can be used to implement all the stuff you've proposed (and more, thanks to its flexibility), without need for extra parameters
https://github.com/ikemen-engine/Ikemen-GO/wiki/Miscellaneous-Info/#arcs