Further update on my rhubarb experiments. Have had further success in making excellent textured ice cream/sorbet using rhubarb and no other texture modifiers/stabilisers. I made a pint of rhubarb base by bringing a pound of rhubarb, a cup of sugar and enough water to cover it to a boil, then turning off the heat. Once that was cooled it was split evenly between 2 Creami pints.
Pint 1 was topped up with canned peaches and a little bit of the syrup they came packed in. This was frozen as is with chunks and peach slices.
Pint 2 was topped up with strawberry kefir that had some heavy cream poured into it a few days prior, so fermented half and half, in essence. This got buzzed with the stick blender to mash everything up.
Both frozen for about 36 hours, then processed. The creamy one on the ice cream setting and the all fruit one on the sorbet setting. Both had excellent texture.
I'm glad that my local Wegmans stocks rhubarb year round.