Hal is one of the League founder
Dick was the first sidekick and still is the trainer for young heroes
Wally is the former sidekick who grew to hold the legacy mantle for the longest time
Yeah they're pretty much perfect
Though maybe if it's not Hal it can be any of the founder, Hal is just so happen to be a founder that's not on the League right now
Wait no nevermind it has to be Hal because the other founders have sidekicks that are now part of the Legacy feature. The Corps don't