Thank you for sharing your success story with using the Fleshlight sex toy to help your partner get beyond the fast friction hand-job.
If you want to increase the intensity of your orgasms, edging - getting in front of an orgasm and holding back - will do the trick.
Stay with your hands for a slower buildup and keep going. You'll get there.
If you practice edging, building up and pulling back to increase sexual tension, one BIG one is quite enough for most of us.
Most women can't orgasm from penetration alone. Your clitoris is your primary sex organ.
You would get more out of masturbation by doing it less and spending more time "edging" or holding off your orgasm.
You'll just have to add fantasy and maybe some sex toys later on to keep it lively.