There's nothing wrong with having a female character who is predominantly a burglar and a hero when the need arises opening using what is unquestionably a hot body and a pretty face to accomplish what she needs.
Because of her father not being around a lot of the time, Felicia has issues with not having a male figure around to guide her. The one time she did let her guard down, she was raped and therefore her wish for a male figure became even more hard to attain due to trust, but still desired. This has lead to insecurity issues about herself in general as she subconsciously sees herself as someone that is incapable of holding onto anything that matters and therefore it must be her that causes that loss. This is why she is aware she is hot, but also worries that as her hotness gets her the spotlight, if she were ever to lose that beauty she would lose the attention. The attention is what she craves now as a substitute for retaining affection and meaningful feelings from someone.
This is why she flaunts her boobage, but at the same time resents any implication that she might be bursting out of her costume and therefore getting fat. This is why she still sees Peter as the man for her as he is without question the only man who provides both guidance like she needed from her father, and compassion like she needed from the guy who raped her but proved to be only after the body she now so openly uses against anyone she comes up against.
Felicia has depth beyond that of her cleavage. The stories she is used in just illustrate her sexuality and leave out anything that moves her forward. Her appearances have been brief but frequent of late and therefore there are two choices when using her in a script. Explore the character within the existing story (only possible when not a cameo), or use her physicality to add humour to a darker story by focussing on her hotness as a foil.
If she is brought in as more of a friend figure to MJ (as I'm not seeing Jessica hanging with MJ in Avengers tower in any appearance), then it brings Felicia more into the mainstream MU (though she has run into more characters of late than ever before) and allows the chance to show her humanity a bit more than her body, but still has her body front and centre from a visual perspective.