I miss my hoya, it was my grandmothers and was a faithful bloomer with a wonderful scent. It somehow got lost in the move I guess. As for you're ionantha I think your right on the I.D. I wish Sun Room was still around, she gave me alot of great info and ideas.
I had a Hoya once... A seedling taken from the mother plant my mother inherited from her mother, in other words; a rather old Hoya (it must be 50-60 years old now).
It was pretty but it never bloomed for me (my mother's is almost always blooming to her great distress - she has got asthma so she's sensitive to intense fragrances).
So a blooming Hoya is strongly connected to my childhood memories, thanks for sharing.