Honestly this could help though. Part of fleshing out a character means giving them a universe/recurring characters that mean something for them to develop alongside. Most of the marvel's biggest characters have families/children. Blade's issue is he was introduced as a side character and they kept killing off everyone that meant anything to him to further drive him mad. I was doing a re-read a while back of all of Blade's stories, and it was similar to Wolverine how many of his bigger stories just end with everyone he cares about dead. Quincy Harkers vampire slayers, the nightstalkers, the brothel he was raised, damn near all of his girlfriends, etc.
I think if they genuinely use this as an opportunity to add some emotional depth to him, that could be good. I think we're all just worried about them just tossing him aside if she gets more popular. I have a feeling she'll be well received too. She's built with the newer age of horror comics in mind.