GRX 825 lower gearing

Hi, I would like to get electronic shifting on my bike and consider the GRX825 2x system, cause I live in a flat area. Although I like to travel to the alps to do extreme routes, where I used my current setup with a mechanical GRX 812 2×11 with a 14-42 in the back.

Now my question: Has anyone figured out the max capabilities of the current GRX 2x lineup?

As far as I know, those chainrings 44-28 are my best option in the front. Are there high quality options for the rear ?

https://specialites-ta.com/double/440-1792-plateau-gravel-specialites-ta-x110-grx-2-10-11-12v-exterieur-specialites-ta-pl481103g9.html#/25,denture,44-dts

Thanks in advance