"But I think it's fair to say that Sega didn't "value" characters and their worth very highly in terms of how marketable they were. Instead they treat a character as something that was created, used and disposed." Yasuhara in the 2018 postmortem
Sticks' confirmation in IDW is a bit iffy at the moment since Ian needs to double check with the higher-ups to see if it's okay. She had official artwork posted on Sonic Channel and was featured in one of the "Mario & Sonic" titles, but that was back when "Boom" was still airing. Now that the show might've ended, it's possible that she might no longer be considered relevant.
Ah the inevitable character's family in expanded media. It's never done "right" but is never really done "wrong" either. Either we have characters that would be interesting but never explored, dumb characters that appear too often, or characters that even though have potential, take away from the existing charac ter.
Example Tails's parents: Firstly, other than their pointless rebellion (Let's be fair, nobody had a problem with the Monarchy until they needed one, so it comes outta nowhere and ultimately goes nowhere as nobody listens to the new rules anyways), you forget they're even there. And when they're there they're only to cause conflict not make Tails grow as a character. Secondly Tails's character from the start was Sonic's "little bro" and his family was always the Freedom Fighters. It kinda takes away his tragic backstory if he instantly gets along with his parents and just accepts they're now part of his life. It honestly would have been more interesting if Tails sided against his parents in the rebellion. They could all grow on different political ideals and learn to come together over conflict.
Also Jules and Bernadette were awesome parents to Tails. They deserve better than "Oh hey my real parents are here, bye."
Personally, I don't like the idea of not including any kind of familial relationships...at least in the comics. The games are fine as games are supposed to be more about gameplay rather than story, but redacting Sonic so no family is around takes way too much away from his character for the narrative to work.