try shooting the rubber parts with spray silicone to puff them up. they should pop open further afterwards.

 

small heavy duty spring in the doorjam would work just as well but make harder to close the door..Uve been watchin that Steve Martin movie havnt ya??just yell "hey baby" and the door opens???

 

Don't you still need to get out to shut the door after she gets in ?
Maybe you could attach as strap that either you or she could pull to shut the door back ?
Maybe I am still missing something ?
You do have a cool idea .