I highly recommend the Amethyst
or the Bent Graduate
. The Bent Graduate comes with better storage, but aside from that, they're the same toy. I'd pick on whether you like pink or purple more. The shape of the Amethyst and the Bent Graduate have easily been amazing for me. They're probably my favorite glass toys (favorite dildos, period, actually).
A more luxurious glass g-spot toy is the Luxotiq Athena
. If your g-spot is more sensitive or if you had no problems reaching it with the Kissa, this one is nice.
The B2B G-Spot
glass g-spot toy also resembles the Amethyst and Bent Graduate, but it's clear and has some different textures on it.
If you'd be okay with a glass-*like* toy, these two Lucite dildos work great as well: Crystal Wand
and Deluxe Crystal Wand
. Lucite is lighter than glass, but it has the same strength, firmness, and slickness.
All of the mentioned are good options, but my "baby" is still the Bent Graduate.
I'm in love with it.
Here are other resources for you:
All Glass Dildos
All SSA Glass Dildos (which are amazingly affordable)
Other Glass Vibrators like the Kissa
Let me know if you have any other questions!