Finding the G-spot is a talent that takes practice so you might as well start going on the hunt now. Also introducing a pocket rocket or a cock ring would definitely be a smooth way to introduce toys into the sex life.
I've had a personal experience with a girl who absolutely hated blowjobs. in the year and a half i dated her she only gave me probably a total of 10 blowjobs ( i had her doing open to alot of other stuff but that just wasnt her thing ). i think the most important think is not to force her to let you try to finish when shes doing it to you. or start with maybe finishing on her chest or something like that and she might let down her guard and then be more open to it in the future.. i hope this is decent advice