Researching for Season 4, Episode 20: “Bounty” and found a little info about Boba Fett’s armor.
Dave Filoni had stated:
“Rather than use his father’s armor, which would still be a tad big for him, we gave him his own unique helmet and armor. It’s a step towards who he will become, but to get to the final famous look from the films, he will need to get some help…”
This was to be planned in Season 7, where Boba Fett would finally don the iconic armor, fighting alongside many recognizable bounty hunters from his old group, including Cad Bane.