Well, Goku and Chichi were inspired by Kishimoto to do Naruto in the first place. Chichi and Hinata are alike you just need to look at the earlier episodes of DB.
Chichi was shy and liked the main character, and wasn't the main heroine, just like Hinata. Bulma closely resembles Sakura, the way they have short tempers, brightly colored hair, etc. Just how Sasuke shares some things in common with Vegeta, so its not really that far fetched.
Actually, Kishimoto followed his pairings through thick and thin, he admitted at one point Hinata would have made a better heroine than Sakura. You know its bad when an author has to admit that sort of thing, so of course he had to give Hinata more moments to better fit his vision of the path he wanted both pairings to go by. "Barely had any importance to the story." Wrong again, if Hinata didn't risk her life to save Naruto, then Naruto wouldn't have gone nine tails, and he wouldn't have met his parents, Naruto would have basically ended there. Or he could have agreed with Obito and given up right then and there if Hinata wasn't there to slap him back to his senses. So I'd say she was very much important to the story.