I don't dislike Asuka, but I agree. She's getting pushed pretty hard as a part of the main cast through continuous appearances, but doesn't have the level development that Tomoko/Yuri/Nemo have. To be fair though, the build up for the other 3 was very gradual and I'd like to believe the same thing is being done for Asuka. The setup is clearly there (some anon even made a whole essay about it, but I didn't save the link) but so far all we know about her is that she's a super nice girl who takes an interest in Tomoko after she gets Nemo and Akane to make up from their quarrel during "Disney"land.
Pic related is also interesting (it's from the chapter right after Disneyland) since you have the current main cast, and then there's Minami behind Yuri. I feel like it implies Minami will be relevant soon or at the very least she'll get something.